diff --git a/rhino/rhinopanel.py b/rhino/rhinopanel.py
index 52478a6..47dfeb7 100644
--- a/rhino/rhinopanel.py
+++ b/rhino/rhinopanel.py
@@ -1080,6 +1080,8 @@ class EbenenBridge(panel_base.BaseBridge):
         def on_save(updated):
             doc2 = Rhino.RhinoDoc.ActiveDoc
             if doc2 is None: return
+            # Snapshot OLD settings VOR dem Save fuer Stale-Detection
+            old_settings = load_project_settings(doc2) or {}
             new_settings = {
                 "defaults":    updated.get("defaults", {}),
                 "materials":   updated.get("materials", []),
@@ -1102,33 +1104,79 @@ class EbenenBridge(panel_base.BaseBridge):
                 if eb is not None: eb._send_state()
             except Exception as ex:
                 print("[PROJECT-SETTINGS] elemente refresh:", ex)
-            # Alle wand_axis im Doc regenen damit Material-Aenderungen
-            # (PBR/Texturen/Hatch) auf existing Waende durchschlagen.
+            # Stale-Detection: welche Wand-Styles oder Materials haben sich
+            # geaendert? Nur betroffene Waende regenen (statt alle).
             try:
                 import elemente
-                undo_serial = doc2.BeginUndoRecord("Material-Update Regen")
-                prev_redraw = doc2.Views.RedrawEnabled
-                doc2.Views.RedrawEnabled = False
+                old_styles = {s.get("id"): s for s in
+                              (old_settings.get("wand_styles") or [])
+                              if isinstance(s, dict) and s.get("id")}
+                new_styles = {s.get("id"): s for s in
+                              (new_settings.get("wand_styles") or [])
+                              if isinstance(s, dict) and s.get("id")}
+                changed_style_ids = set()
+                for sid in (set(old_styles) | set(new_styles)):
+                    if old_styles.get(sid) != new_styles.get(sid):
+                        changed_style_ids.add(sid)
+                old_mats = {m.get("name"): m for m in
+                            (old_settings.get("materials") or [])
+                            if isinstance(m, dict) and m.get("name")}
+                new_mats = {m.get("name"): m for m in
+                            (new_settings.get("materials") or [])
+                            if isinstance(m, dict) and m.get("name")}
+                changed_material_names = set()
+                for n in (set(old_mats) | set(new_mats)):
+                    if old_mats.get(n) != new_mats.get(n):
+                        changed_material_names.add(n)
+                # Welche Waende sind betroffen?
                 wall_ids = []
+                seen = set()
                 for obj in doc2.Objects:
                     m = elemente._read_meta(obj)
-                    if m and m.get("type") == "wand_axis":
-                        wall_ids.append(m["id"])
-                # Chain-Anchor regent automatisch alle members — wir koennen
-                # trotzdem alle einzeln triggern, _REGEN_BUSY-Guard verhindert
-                # Doppel-Arbeit. Einfacher als Anchor-Election hier.
+                    if not m or m.get("type") != "wand_axis": continue
+                    wid = m["id"]
+                    if wid in seen: continue
+                    affected = False
+                    sid = (m.get("wand_style_id") or "").strip()
+                    if sid and sid in changed_style_ids:
+                        affected = True
+                    if not affected and m.get("wand_layered"):
+                        for layer in (m.get("wand_layers") or []):
+                            if isinstance(layer, dict) and layer.get("material") \
+                                    in changed_material_names:
+                                affected = True; break
+                    if not affected and sid and changed_material_names:
+                        # Solid-Wand mit Style: Material-Aenderung des
+                        # Style-referenzierten Materials trifft sie
+                        st = new_styles.get(sid) or old_styles.get(sid)
+                        if st and st.get("material") in changed_material_names:
+                            affected = True
+                    if affected:
+                        wall_ids.append(wid); seen.add(wid)
+                if not wall_ids:
+                    print("[PROJECT-SETTINGS] keine wand-relevanten Aenderungen")
+                    return
+                undo_serial = doc2.BeginUndoRecord(
+                    "Stil-Update Regen ({})".format(len(wall_ids)))
+                prev_redraw = doc2.Views.RedrawEnabled
+                doc2.Views.RedrawEnabled = False
                 try:
+                    sc.sticky["_dossier_regen_batch_active"] = True
                     for wid in wall_ids:
                         try: elemente._regenerate_element(doc2, wid)
                         except Exception as ex:
                             print("[PROJECT-SETTINGS] regen", wid, ex)
                 finally:
+                    sc.sticky["_dossier_regen_batch_active"] = False
                     doc2.Views.RedrawEnabled = prev_redraw
                     try: doc2.EndUndoRecord(undo_serial)
                     except Exception: pass
                 try: doc2.Views.Redraw()
                 except Exception: pass
-                print("[PROJECT-SETTINGS] {} Waende regenert".format(len(wall_ids)))
+                print("[PROJECT-SETTINGS] {} Waende regenert ({} Stile, "
+                      "{} Materials geaendert)".format(
+                          len(wall_ids), len(changed_style_ids),
+                          len(changed_material_names)))
             except Exception as ex:
                 print("[PROJECT-SETTINGS] wall regen:", ex)
         # Custom-Bridge fuer Project-Settings: handelt SAVE/CANCEL +