diff --git a/CHANGELOG.md b/CHANGELOG.md
index a2da18f..235988d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -21,9 +21,13 @@ All notable changes to Splat Workshop. The format follows [Keep a Changelog](htt
 - **1 M splats is the recommended size for the Frame** (preselected for versions and tours, also the default of `combine.sh`, was 3.5 M). Measured on a Steam Frame with one tour: 0.75 M 36 fps, 1 M 35 fps, 1.5 M 29 fps, 2 M 24 fps, 5 M 14 fps – 1 M looked clearly sharper than 0.75 M, 1.5 M a little sharper but already slightly unsteady. All sizes stay selectable.
 - Putting a tour together offers 0.75 to 2 M splats or an own size for its Frame version (was 2 / 3.5 / 5 M).
 
+- Tests extended after an independent review with mutation testing (499 including the type checks of every request field): scale, versions, fetching several recordings, deleting recordings, the *On the Frame* tab and the new folder, and what is locked while a scene is computed, checked, fetched or copied.
+
 ### Fixed
 
 - The floor plan no longer fails for scenes in which it finds no walls (e.g. a model without its scale).
+- The floor plan of a group uses the group's scale, also when it was not passed on to its scenes. Scenes in different scales without one for the group give a clear message instead of a plan in the wrong size.
+- *Move to own scenes* waits until no scene is being copied to the Frame.
 
 ## [0.2.2] – 2026-10-14
 
diff --git a/splat_workshop/server.py b/splat_workshop/server.py
index 97888a1..c4056a5 100644
--- a/splat_workshop/server.py
+++ b/splat_workshop/server.py
@@ -1027,10 +1027,9 @@ def move_to_own_folder():
     gallery = frame_gallery(force=True)
     if gallery is None:
         return err("err.frame_offline")
-    moving = [g for g in gallery if g["place"] == "steam" and g["kind"] != "other"]
-    if any((u := uploads.get(f"{g['slug']}#{g['version']}" if g["version"] else g["slug"])) and u["proc"].poll() is None
-           for g in moving):
+    if any(u["proc"].poll() is None for u in uploads.values()):    # to-frame.sh may be choosing or moving a folder
         return err("err.upload_busy")
+    moving = [g for g in gallery if g["place"] == "steam" and g["kind"] != "other"]
     if not moving:
         return None
     # A folder of the same name in the personal folder is the newer copy: the old one goes
@@ -1230,8 +1229,9 @@ def scenes():
 plan_locks = {}                    # cache key -> Lock, so one plan is drawn only once at a time
 
 
-def floorplan(slugs: list[str], style: str, lang: str, title: str):
-    """(PNG bytes, info dict with pixels_per_metre) of one or more scenes (cached), or an error dict."""
+def floorplan(slugs: list[str], style: str, lang: str, title: str, group: str = ""):
+    """(PNG bytes, info dict with pixels_per_metre) of one or more scenes (cached), or an error dict.
+    The plan of a group is drawn in the group's scale, if it has one; otherwise all scenes need the same."""
     if style not in ("pretty", "classic"):
         style = "pretty"
     runs = []
@@ -1243,8 +1243,16 @@ def floorplan(slugs: list[str], style: str, lang: str, title: str):
         runs.append((d, read_meta(slug).get("name") or slug, ply.stat().st_mtime))
     if not runs or len(runs) > 12:
         return err("err.bad_request")
-    scales = {read_meta(slug).get("scale") or 1 for slug in dict.fromkeys(slugs)}
-    ratio = scales.pop() if len(scales) == 1 else 1
+    gmeta = read_meta(group) if group and Path(group).name == group and not group.startswith(".") else {}
+    if gmeta and not is_group(gmeta):
+        return err("err.bad_request")
+    if (gmeta.get("scale") or 1) != 1:
+        ratio = gmeta["scale"]
+    else:
+        scales = {read_meta(slug).get("scale") or 1 for slug in dict.fromkeys(slugs)}
+        if len(scales) > 1:
+            return err("err.mixed_scale")
+        ratio = scales.pop()
     title = title.strip()[:60]
     script = (SCRIPTS / "floorplan.py").stat().st_mtime        # a new version of the script draws anew
     key = hashlib.sha1(json.dumps([[str(r[0]), r[1], r[2]] for r in runs] + [style, lang, title, script, ratio]).encode()).hexdigest()[:16]
@@ -1981,7 +1989,7 @@ class Handler(http.server.BaseHTTPRequestHandler):
             return self.send(200, {"versions": versions_of(q.get("slug", ""))})
         if u.path == "/api/floorplan":
             data = floorplan([x for x in q.get("slugs", "").split(",") if x], q.get("style", "pretty"),
-                             q.get("lang", "en"), q.get("title", ""))
+                             q.get("lang", "en"), q.get("title", ""), q.get("group", ""))
             if isinstance(data, dict):
                 return self.send(400, {"error": data})
             data, info = data
diff --git a/tests/conftest.py b/tests/conftest.py
index 8169d17..951ac40 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -135,6 +135,10 @@ if os.environ.get("FAKE_FRAME_CUT") and cmd.startswith("cat "):   # the connecti
     out = subprocess.run(["bash", "-c", cmd], cwd="{FRAME_HOME}", env=env, capture_output=True).stdout
     sys.stdout.buffer.write(out[:len(out) // 2])
     sys.exit(255)
+if os.environ.get("FAKE_FRAME_SHORT") and cmd.startswith("cat "):  # ends early, but without an error
+    out = subprocess.run(["bash", "-c", cmd], cwd="{FRAME_HOME}", env=env, capture_output=True).stdout
+    sys.stdout.buffer.write(out[:len(out) // 2])
+    sys.exit(0)
 if os.environ.get("FAKE_FRAME_SLOW") and cmd.startswith("cat "):  # a slow connection: 1 kB every 0.1 s
     import time
     out = subprocess.run(["bash", "-c", cmd], cwd="{FRAME_HOME}", env=env, capture_output=True).stdout
@@ -154,6 +158,9 @@ def local(a):
         return Path("{FRAME_HOME}") / a.split(":", 1)[1]
     return Path(a)
 *src, dst = map(local, args)
+if os.environ.get("FAKE_SCP_SLOW"):                       # a slow connection: copying takes 3 s
+    import time
+    time.sleep(3)
 for s in src:
     shutil.copy(s, dst / s.name if dst.is_dir() else dst)
 ''')
@@ -197,7 +204,8 @@ def clean():
         while server.download_busy() and time.time() < end:
             time.sleep(0.05)
     server.download, server.download_queue[:], server.download_batch = None, [], {}
-    for k in ("FAKE_PIPELINE", "FAKE_FRAME_OFF", "FAKE_FRAME_CUT", "FAKE_FRAME_SLOW", "FRAME_HOST"):
+    for k in ("FAKE_PIPELINE", "FAKE_FRAME_OFF", "FAKE_FRAME_CUT", "FAKE_FRAME_SLOW", "FAKE_FRAME_SHORT", "FAKE_SCP_SLOW",
+              "FRAME_HOST"):
         os.environ.pop(k, None)
     os.environ["FRAME_HOST"] = ""
     TOOL_LOG.unlink(missing_ok=True)
diff --git a/tests/test_jobs.py b/tests/test_jobs.py
index 4e06769..a0b22b2 100644
--- a/tests/test_jobs.py
+++ b/tests/test_jobs.py
@@ -154,6 +154,21 @@ def test_a_scene_being_computed_cannot_be_changed(api):
                        ("/api/clean", {"slug": "Kitchen", "what": "temp"})):
         status, r = api.post(path, body)
         assert status == 400 and r["error"]["code"] == "err.scene_busy", path
+    # the new actions of 0.2.3 leave it alone, too
+    v = RUNS / "Kitchen" / "versions" / "0.01m"
+    v.mkdir(parents=True)
+    (v / "scene.sog").write_bytes(b"x")
+    (v / "version.json").write_text(json.dumps({"key": "0.01m", "splats": 10000, "scale": 1, "label": "Kitchen · 0.01 M"}))
+    for path, body, code in (("/api/scale", {"slug": "Kitchen", "scale": "87"}, "err.scene_busy"),
+                             ("/api/version/delete", {"slug": "Kitchen", "version": "0.01m"}, "err.scene_busy"),
+                             ("/api/versions", {"slug": "Kitchen", "sizes": "10000"}, "err.job_busy")):
+        status, r = api.post(path, body)
+        assert status == 400 and r["error"]["code"] == code, path
+    assert v.is_dir() and not (server.read_meta("Kitchen").get("scale") or 1) - 1
+    # and its recording stays
+    rec = server.load_state()["job"]["recording"]
+    status, r = api.post("/api/recording/delete", {"name": rec, "where": "pc"})
+    assert status == 400 and r["error"]["code"] == "err.recording_busy" and (server.REC / rec).exists()
     # and no tour is put together meanwhile (one job at a time)
     synth.make_room(RUNS, "Office", "A")
     synth.make_room(RUNS, "Hallway", "B")
diff --git a/tests/test_recordings.py b/tests/test_recordings.py
index b258fc4..1ebd0aa 100644
--- a/tests/test_recordings.py
+++ b/tests/test_recordings.py
@@ -299,3 +299,23 @@ def test_deleting_on_a_frame_that_is_off(api, frame):
     os.environ["FAKE_FRAME_OFF"] = "1"
     status, r = api.post("/api/recording/delete", {"name": name, "where": "frame"})
     assert status == 400 and r["error"]["code"] == "err.frame_offline"
+
+
+def test_a_recording_being_checked_is_not_deleted(api, frame):
+    rec = recording()
+    put_on_frame(frame, rec.name)
+    server.checks[rec.name] = {"state": "running"}
+    for where in ("pc", "frame"):
+        status, r = api.post("/api/recording/delete", {"name": rec.name, "where": where})
+        assert status == 400 and r["error"]["code"] == "err.recording_busy", where
+    assert rec.exists() and (frame / VIDEOS / rec.name).exists()
+
+
+def test_a_download_that_ends_too_early_leaves_nothing_behind(api, frame):
+    name, _ = put_on_frame(frame)
+    server.frame_listing(force=True)
+    os.environ["FAKE_FRAME_SHORT"] = "1"                 # half the file, but no error from ssh
+    assert api.post("/api/download", {"name": name})[0] == 200
+    st = wait_fetched()
+    assert st["error"] and st["batch"]["failed"] == [name]
+    assert not (REC / name).exists() and not (REC / (name + ".part")).exists()
diff --git a/tests/test_scale.py b/tests/test_scale.py
index 488d321..2d48ab4 100644
--- a/tests/test_scale.py
+++ b/tests/test_scale.py
@@ -123,3 +123,29 @@ def test_a_tour_of_a_model_is_walkable_in_both_versions():
     tour = RUNS / "Layout"
     assert json.loads((tour / "layout.xrSceneTransform.json").read_text())["worldScale"] == H0
     assert json.loads((tour / "full" / "layout-full.xrSceneTransform.json").read_text())["worldScale"] == H0
+
+
+def test_the_floor_plan_of_a_group_in_the_groups_scale(api):
+    synth.make_room(RUNS, "Station", "A", error=(0.0, (0, 0, 0)), scale=1 / H0)
+    server.save_group("", "Layout", "Station")
+    api.post("/api/scale", {"slug": "Layout", "scale": str(H0)})         # only on the group, not passed on
+    assert {x["slug"]: x["scale"] for x in api.get("/api/scenes")[1]}["Station"] == 1
+    full = plan(synth.make_room(BASE / "full", "Room", "A", error=(0.0, (0, 0, 0))))
+    info = server.floorplan(["Station"], "classic", "en", "", "Layout")[1]
+    assert info["ratio"] == H0
+    assert info["scenes"][0]["size"] == pytest.approx(full["scenes"][0]["size"], abs=0.05)       # 4 x 3 m
+    status, png = api.get("/api/floorplan?slugs=Station&style=classic&group=Layout")
+    assert status == 200 and png[:4] == b"\x89PNG"
+    assert server.floorplan(["Station"], "classic", "en", "", "Station")["code"] == "err.bad_request"   # not a group
+
+
+def test_a_floor_plan_of_scenes_in_different_scales_is_refused(api):
+    synth.make_room(RUNS, "Station", "A", recording="2026-10-12_16-40-00_stereo.mp4")
+    synth.make_room(RUNS, "Yard", "B", recording="2026-10-12_16-43-00_stereo.mp4")
+    server.save_group("", "Layout", "Station,Yard")
+    api.post("/api/scale", {"slug": "Station", "scale": "87"})
+    api.post("/api/scale", {"slug": "Yard", "scale": "160"})
+    status, r = api.get("/api/floorplan?slugs=Station,Yard&group=Layout")
+    assert status == 400 and r["error"]["code"] == "err.mixed_scale"
+    api.post("/api/scale", {"slug": "Layout", "scale": "87"})            # one scale for the group decides
+    assert api.get("/api/floorplan?slugs=Station,Yard&style=classic&group=Layout")[0] == 200
diff --git a/tests/test_security.py b/tests/test_security.py
index 75c9d3b..716e9f1 100644
--- a/tests/test_security.py
+++ b/tests/test_security.py
@@ -126,11 +126,15 @@ def test_from_this_pc_means_loopback():
 
 
 ENDPOINTS = ["/api/start", "/api/rename", "/api/clean", "/api/delete", "/api/upload", "/api/download", "/api/check",
-             "/api/group", "/api/group/dismiss", "/api/combine", "/api/resume"]
+             "/api/group", "/api/group/dismiss", "/api/combine", "/api/resume", "/api/versions", "/api/scale",
+             "/api/frame/remove", "/api/frame/move", "/api/recording/delete", "/api/version/delete",
+             "/api/download/cancel"]
 
 
 @pytest.mark.parametrize("path", ENDPOINTS)
-@pytest.mark.parametrize("field", ["name", "new", "slug", "path", "what", "members", "key", "align", "quality"])
+@pytest.mark.parametrize("field", ["name", "new", "slug", "path", "what", "members", "key", "align", "quality",
+                                   "existing", "partition", "version", "sizes", "scales", "folder", "names", "place",
+                                   "where"])
 def test_wrongly_typed_fields_get_400_everywhere(api, path, field):
     for bad in (5, ["a"], True):
         assert api.post(path, {field: bad})[0] == 400, (path, field, bad)
diff --git a/tests/test_versions.py b/tests/test_versions.py
index 677d43b..5a617aa 100644
--- a/tests/test_versions.py
+++ b/tests/test_versions.py
@@ -177,3 +177,44 @@ def test_taking_off_a_frame_that_is_off(api, frame):
     assert status == 400 and r["error"]["code"] == "err.frame_offline"
     os.environ.pop("FAKE_FRAME_OFF")
     assert (frame / server.FRAME_SCENES / "20_Room-0.01m").exists()
+
+
+def test_versions_sh_refuses_odd_version_names():
+    import subprocess
+    from conftest import ROOT
+    run, _ = room()
+    for spec in ("../x|10000|1|x", ".hidden|10000|1|x", "a/b|10000|1|x"):
+        r = subprocess.run([str(ROOT / "scripts" / "versions.sh"), str(run), spec], capture_output=True, text=True)
+        assert r.returncode == 1 and "Unusable version name" in r.stderr, spec
+    assert not (run / "x").exists() and not (run / "versions").exists()
+
+
+def test_an_old_copy_of_a_version_is_recognised_by_its_folder(api, frame):
+    room()
+    make("Room", "10000")                                       # not copied by this version: no version_folders
+    d = frame / server.FRAME_STEAM / "21_Room-0.01m"
+    d.mkdir()
+    (d / "room-0.01m.gallery.png").write_bytes(b"preview")
+    server.frame_cache["t"] = 0
+    assert server.versions_of("Room")[0]["on_frame"] is True
+    g = {x["folder"]: x for x in api.get("/api/frame/gallery?refresh=1")[1]["scenes"]}["21_Room-0.01m"]
+    assert (g["kind"], g["slug"], g["version"], g["place"]) == ("version", "Room", "0.01m", "steam")
+
+
+def test_nothing_is_moved_or_removed_on_the_frame_while_copying(api, frame):
+    room()
+    make("Room", "10000")
+    d = frame / server.FRAME_STEAM / "20_Room-0.01m"            # an old copy, being copied again right now
+    d.mkdir()
+    (d / "room-0.01m.gallery.png").write_bytes(b"preview")
+    os.environ["FAKE_SCP_SLOW"] = "1"
+    assert api.post("/api/upload", {"slug": "Room", "version": "0.01m"})[0] == 200
+    time.sleep(0.5)
+    for path, body in (("/api/frame/move", {}), ("/api/frame/remove", {"folder": "20_Room-0.01m"}),
+                       ("/api/version/delete", {"slug": "Room", "version": "0.01m"})):
+        status, r = api.post(path, body)
+        assert status == 400 and r["error"]["code"] in ("err.upload_busy", "err.scene_busy"), path
+    end = time.time() + 30
+    while (u := server.upload_status("Room#0.01m")) and u["running"] and time.time() < end:
+        time.sleep(0.2)
+    assert server.upload_status("Room#0.01m")["ok"]
diff --git a/web/i18n.js b/web/i18n.js
index 001ab09..76ddbed 100644
--- a/web/i18n.js
+++ b/web/i18n.js
@@ -232,7 +232,7 @@ const I18N = {
     "fg.move.hint": "{n} scene(s) from Splat Workshop are still in Gaussian XR's own folder, where a Steam update can delete them.",
     "fg.move": "Move to own scenes", "fg.moved": "Moved to the own scenes on the Frame",
     "ver.recommended": "(recommended)",
-    "err.plan_failed": "The floor plan could not be drawn", "sc.replacing": "Being computed again – stays until the new one is done", "err.plan_busy": "Other floor plans are being drawn right now, try again in a moment",
+    "err.mixed_scale": "These scenes have different scales – set one scale for the group", "err.plan_failed": "The floor plan could not be drawn", "sc.replacing": "Being computed again – stays until the new one is done", "err.plan_busy": "Other floor plans are being drawn right now, try again in a moment",
     "plan.measure": "📏 Measure", "plan.measure.title": "Measure distances in the floor plan",
     "plan.measure.hint": "Click to set points · right-click removes the last one · horizontal distances, about ±5 cm",
     "plan.measure.undo": "Undo", "plan.measure.reset": "Reset",
@@ -473,7 +473,7 @@ const I18N = {
     "fg.move.hint": "{n} Szene(n) aus der Werkstatt liegen noch im Ordner von Gaussian XR, wo ein Steam-Update sie löschen kann.",
     "fg.move": "Zu den eigenen Szenen verschieben", "fg.moved": "Zu den eigenen Szenen auf der Frame verschoben",
     "ver.recommended": "(empfohlen)",
-    "err.plan_failed": "Der Grundriss konnte nicht gezeichnet werden", "sc.replacing": "Wird neu gerechnet – bleibt, bis die neue fertig ist", "err.plan_busy": "Gerade werden andere Grundrisse gezeichnet, gleich noch einmal versuchen",
+    "err.mixed_scale": "Die Szenen haben verschiedene Maßstäbe – einen Maßstab für die Gruppe setzen", "err.plan_failed": "Der Grundriss konnte nicht gezeichnet werden", "sc.replacing": "Wird neu gerechnet – bleibt, bis die neue fertig ist", "err.plan_busy": "Gerade werden andere Grundrisse gezeichnet, gleich noch einmal versuchen",
     "plan.measure": "📏 Messen", "plan.measure.title": "Abstände im Grundriss messen",
     "plan.measure.hint": "Klicken setzt Punkte · Rechtsklick nimmt den letzten zurück · waagerechte Abstände, etwa ±5 cm genau",
     "plan.measure.undo": "Rückgängig", "plan.measure.reset": "Zurücksetzen",
diff --git a/web/index.html b/web/index.html
index 4a36316..f0c1a2f 100644
--- a/web/index.html
+++ b/web/index.html
@@ -1034,7 +1034,7 @@ async function loadScenes() {
   document.querySelectorAll("[data-combine]").forEach(b => b.onclick = () => openCombine(S.groups.find(g => g.slug === b.dataset.combine)));
   document.querySelectorAll("[data-gplan]").forEach(b => b.onclick = () => {
     const g = S.groups.find(x => x.slug === b.dataset.gplan);
-    openPlan(g.members.filter(m => bySlug[m] && bySlug[m].ply), g.name);
+    openPlan(g.members.filter(m => bySlug[m] && bySlug[m].ply), g.name, g.slug);
   });
   document.querySelectorAll("[data-upload]").forEach(b => b.onclick = async () => {
     const r = await api("/api/upload", {slug: b.dataset.upload});
@@ -1371,11 +1371,12 @@ const P = {slugs: [], name: "", style: "pretty"};
 function planUrl(download) {
   const q = new URLSearchParams({slugs: P.slugs.join(","), style: P.style, lang: LANG,
                                   title: P.slugs.length > 1 ? P.name : ""});
+  if (P.group) q.set("group", P.group);
   if (download) { q.set("download", "1"); q.set("name", `${P.name}-${tr("plan.file")}`); }
   return "/api/floorplan?" + q;
 }
-function openPlan(slugs, name) {
-  P.slugs = slugs; P.name = name;
+function openPlan(slugs, name, group) {
+  P.slugs = slugs; P.name = name; P.group = group || "";
   $("#planTitle").textContent = tr(slugs.length > 1 ? "plan.title.all" : "plan.title", {name});
   $("#planStyle").classList.remove("hidden"); $("#planSave").classList.remove("hidden"); $("#planMeasure").classList.remove("hidden");
   if (!$("#planDlg").open) $("#planDlg").showModal();