Now I got the source for Kosmon from Olaf Seibert.
Kosmon is for C64 and PET with basic 2/4 and 40/80 columns.
Sadly nearmost all addresses in the original roms are totally different, because of the zero-page-basic-input-buffer!
I have to change a lot of zeropage addresses and kernal-jumps to the original roms.
After the first debugging round it's running (with more bugs):
Working: R, X, M, D
But there are still some bugs to find...
...and I should throw out the floppy part, because it doesn't work with original roms and saves RAM!