diff --git a/__init__.py b/__init__.py
index cdb4d95..2561a5f 100644
--- a/__init__.py
+++ b/__init__.py
@@ -108,7 +108,7 @@ class STOCKER_OT_setup(bpy.types.Operator):
             bounds['size'].z += height_add
             bounds['max'].z += height_add
 
-        # 3. Create the cube (parent to selected instance for tracking)
+        # 3. Create the cube (parent to selected for tracking)
         new_obj = logic.create_aligned_boundary_cube(bounds, parent=selected_objs[0], mode=self.mode)
         if not new_obj:
             self.report({'ERROR'}, "Failed to create boundary cube.")
diff --git a/scripts/phase2_geometry.py b/scripts/phase2_geometry.py
index f1c6842..c4dcd15 100644
--- a/scripts/phase2_geometry.py
+++ b/scripts/phase2_geometry.py
@@ -1,6 +1,25 @@
 import bpy
 import mathutils
 
+def resolve_to_mesh_objects(obj):
+    """Recursively resolve collection instances and linked instances to their source mesh objects."""
+    if obj.type == 'MESH':
+        return [obj]
+    elif obj.type == 'EMPTY' and obj.instance_collection:
+        # Collection instance — walk linked objects
+        result = []
+        for linked_obj in obj.instance_collection.objects:
+            result.extend(resolve_to_mesh_objects(linked_obj))
+        return result
+    elif obj.type == 'MESH' or obj.instance_type != 'NONE':
+        # Linked instance or other instance type — use its data
+        if obj.data and obj.data.type == 'MESH':
+            return [obj]
+        elif hasattr(obj, 'instance_object') and obj.instance_object:
+            return resolve_to_mesh_objects(obj.instance_object)
+    return []
+
+
 def calculate_global_bounds(selected_objects):
     if not selected_objects:
         return None
@@ -10,20 +29,32 @@ def calculate_global_bounds(selected_objects):
 
     found_any_mesh = False
     for obj in selected_objects:
-        if obj.type != 'MESH':
+        mesh_objects = resolve_to_mesh_objects(obj)
+        if not mesh_objects:
             continue
-        
-        found_any_mesh = True
-        matrix = obj.matrix_world
-        for corner in obj.bound_box:
-            world_corner = matrix @ mathutils.Vector(corner)
-            
-            min_x = min(min_x, world_corner.x)
-            min_y = min(min_y, world_corner.y)
-            min_z = min(min_z, world_corner.z)
-            max_x = max(max_x, world_corner.x)
-            max_y = max(max_y, world_corner.y)
-            max_z = max(max_z, world_corner.z)
+
+        for source_obj in mesh_objects:
+            found_any_mesh = True
+
+            if hasattr(source_obj, 'bound_box_world') and source_obj.bound_box_world:
+                bbw = source_obj.bound_box_world
+                for corner in bbw:
+                    min_x = min(min_x, corner.x)
+                    min_y = min(min_y, corner.y)
+                    min_z = min(min_z, corner.z)
+                    max_x = max(max_x, corner.x)
+                    max_y = max(max_y, corner.y)
+                    max_z = max(max_z, corner.z)
+            else:
+                matrix = source_obj.matrix_world
+                for corner in source_obj.bound_box:
+                    world_corner = matrix @ mathutils.Vector(corner)
+                    min_x = min(min_x, world_corner.x)
+                    min_y = min(min_y, world_corner.y)
+                    min_z = min(min_z, world_corner.z)
+                    max_x = max(max_x, world_corner.x)
+                    max_y = max(max_y, world_corner.y)
+                    max_z = max(max_z, world_corner.z)
 
     if not found_any_mesh:
         return None
@@ -34,37 +65,56 @@ def calculate_global_bounds(selected_objects):
         'size': mathutils.Vector((max_x - min_x, max_y - min_y, max_z - min_z))
     }
 
-def create_aligned_boundary_cube(bounds):
+def create_aligned_boundary_cube(bounds, parent=None, mode=None):
     if not bounds:
         return None
 
     min_v = bounds['min']
+    max_v = bounds['max']
     size = bounds['size']
 
     mesh = bpy.data.meshes.new("Stocker_Boundary")
     obj = bpy.data.objects.new("Stocker_Boundary", mesh)
     bpy.context.collection.objects.link(obj)
 
-    verts = [
-        (0, 0, 0),
-        (size.x, 0, 0),
-        (size.x, -size.y, 0),
-        (0, -size.y, 0),
-        (0, 0, size.z),
-        (size.x, 0, size.z),
-        (size.x, -size.y, size.z),
-        (0, -size.y, size.z)
-    ]
+    if mode == 'GRID':
+        # Origin at top-front-left: (min_x, max_y, min_z) — cube extends +X, -Y, +Z
+        obj.location = (min_v.x, max_v.y, min_v.z)
+        verts = [
+            (0, 0, 0),
+            (size.x, 0, 0),
+            (size.x, -size.y, 0),
+            (0, -size.y, 0),
+            (0, 0, size.z),
+            (size.x, 0, size.z),
+            (size.x, -size.y, size.z),
+            (0, -size.y, size.z)
+        ]
+    else:
+        # CIRCLE mode: origin at bottom-front-left
+        obj.location = min_v.copy()
+        verts = [
+            (0, 0, 0),
+            (size.x, 0, 0),
+            (size.x, size.y, 0),
+            (0, size.y, 0),
+            (0, 0, size.z),
+            (size.x, 0, size.z),
+            (size.x, size.y, size.z),
+            (0, size.y, size.z)
+        ]
     faces = [
         (0, 1, 2, 3), (4, 5, 6, 7), (0, 1, 5, 4),
         (1, 2, 6, 5), (2, 3, 7, 6), (3, 0, 4, 7)
     ]
-    
+
     mesh.from_pydata(verts, [], faces)
     mesh.update()
-    
-    # Place origin at Back-Left (Min X, Max Y, Min Z)
-    obj.location = (bounds['min'].x, bounds['max'].y, bounds['min'].z)
+
+    # Parent to selected object so boundary follows instances
+    if parent:
+        obj.parent = parent
+
     return obj
 
 if __name__ == "__main__":