Hey, do you have custom "move" cursor with transform items? For me it slows down too but by changing cursor to default it works okay. It was more like an issue with (dragging/moving?) custom cursors. Even with greensock.com transformmanager demo cursor moves goes very slow when hovering selected transform items with "move" cursor, might be something to do with flash player too... Also I have noticed it depends of browser. For me IE9 works perfectly, Chrome has some minor issues and Firefox is worst for what I have tested. Also I noticed problem with SHIFT + RESIZE ( proportional resize ) with Firefox. It is very slow but with IE9 it works perfectly. Quite interesting...