Thanks for the Information, not what i wantet to hear 
I am in contact with Aerosoft Support, they said nearly the same. Ruder axis left and right are not working on the CRJ.
For taxi it is possible to use the nosewheel, if you use increase and decrease steering via Keyboard.
I hope they will update soon that Ruder axis work, nearly impossible to start without it. Specialy on sidewinds.