How come

my BOX - ROTATION speed is dependent on the MOUSE ICON??

I hope you realise that's a rather cryptic description of your problem.

Are you using a SpatialTransformer in combination with SimpleGame and a very high frame rate? There is currently an issue with this that I'm looking at, for now try using a Thread.sleep(20) or something simulair in simpleUpdate().

What are you talking about? That might be a good place to start.