Hi JD, There is no Chimera command to run an accelerator. Would be handy. I'll add that to the requested feature list. There is no user interface to rename surface pieces. You can do it from Python with code like: plist = m.surfacePieces plist[0].oslName = 'filament 3' Here m is a SurfaceModel object and plist is the list of SurfacePiece objects. Setting the oslName changes the name shown in the popup balloon when the mouse is over that surface piece. There isn't any other code that uses surface piece names (e.g. no dialog that lists the surface piece names to allow you to select them, and no way to select a piece using its name). So the names are currently not too useful. Also there is no file format for saving the surface pieces. Lots of limitations. Tom