Hi, I have found this 1541 II rom:
_A version of the 1541-II ROM where the modifications to older firmware have been relocated to the lower bank ($c000-$dfff), to improve compatibility with fastloader systems. Made by Wolfgang Moser._
Is it possible implement this version, I can't put it in the rom screen. Maybe this can resolve some incompatibilities with fastloaders.
Info: http://www.zimmers.net/anonftp/pub/cbm/firmware/drives/new/1541/hacks/1541-II-relocated.txt
I've added the Rom file signature (magic bytes), so the file is recognised as a VC1541 Rom. I've also added it's hash value to the list of known Roms:

Feature is available in V3.3 alpha 1:
http://www.dirkwhoffmann.de/virtualc64/VirtualC64_3.3_alpha1.zip
Please reopen if there is still an issue.
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I've added the Rom file signature (magic bytes), so the file is recognised as a VC1541 Rom. I've also added it's hash value to the list of known Roms: