I can now delete previous assigned (automatically) control interfaces by considering the hints from this outline: http://support.apple.com/kb/HT5859 , item 8.4 .
But its still the same for the ACT function of the Roland masterkeyboard, sliders and transport buttons play sounds and does not control what they intended for...
Ok, I got it solved:
- missing the context menu in the control interface setup where confusing me and is obviously a bug...the software seems to have some problems with its used windows manager, this is a focus event problem: hitting the right mouse click brings not always the context menu up
- with the Roland masterkeyboard when all 4 Bx buttons lit, turned off the ACT mode, hold a Bx key and press again: the transport sections, faders and so on are working as expected