I remember playing and enjoying this game a lot but I also do remeber that I played it at least with German menus. Any chance to get German text for this as well?

Pretty sure it had french too.

But it's probably Fun Tracks, the French/German version of the game. I wonder if they'll make it available as a separate download.

I've compared my German version with the GOG release:
1. Different logo in the menu. It does have completely different art style and obviously doesn't say Ignition but Bleifuss Fun.
2. German text.
3. CD has a Bleifuss Rally demo, heh.
4. A "MANUAL" folder on the CD with a manual for...Bleifuss Rally. Wait what?

Other than that I don't see any obvious differences. I was able to create an *.iso file from my CD though a complete image with the music tracks wasn't possible. Apparently my old CD has bad sectors (or some copy protection I'm not aware of).

Have you tried using a different format when creating the image (like .bin/.cue)? Because .iso doesn't support audio track CDs, so you'd naturally end up without the music data.

Yes, I tried this after the successful *.iso creation but then got the error. :(

I guess its a problem with your disc then (or your CD drive) because I had no problem creating my bin/cue image using Imgburn and as far as I know the game had no copy protection.