The problem looks like not-compatible graphics mode.
I found ADF disk image, made a floppy disk and tried it on my 1.3 NTSC ECS A500 and it did not work. I tried NTSC and PAL, both modes did not work. My A500 is a modified to 1MB Chip RAM with PAL/NTSC switch.
Then I tried my NTSC A1000 with 512KB chip ram and it did boot to a star-field but later froze.
So, Since the game is from 1987 and German, I'm thinking that it should work on PAL with 512k RAM. Maybe OCS not ECS.
On A1200 I have exactly same visual problem. Graphics are distorted.
I hope it helps.
