PARTS tab

• Mesh Pivot & Geometry Prep: pivot snaps, Edit Pivot (P) with Apply (Enter) / Cancel (Esc), Mesh Scale with Apply Scale (bakes into all LODs, Nanite source, sockets and collision).
• Pick Mode & Scope: Island, Material, PolyGroup, Triangle, Smooth (angle), Brush (B). Scope: Mesh, Part, Free.
• Selection Tools & Visibility: All, Invert, Clear, Unassigned, In Part, Grow / Shrink, Attached +, Orphans, Hide, Isolate, Unhide All.
• Part Creation & Auto-Split: New Part from Selection, Add to Part, Remove from Parts, Clear All Parts, split by Islands, Materials or PolyGroups (Shift: selection only).
• Double-click a part in the viewport to select all of it; Ctrl+A selects the whole part of the selection (again: the whole mesh).
• Configured Mesh Parts, one row per part: visibility, colour (every part gets its own colour; click the swatch to change it), name (F2), role (Rigid, Core, Mid, Outer), Follow, Grass, Wind scale, Select, delete.