@Pio
I dont know how many NoCD cracks there are for DTM? When I used to play it I never updated to v1.02 (I think it is) as there wasnt a NoCD crack for that particular version! But the main reason I didnt update is because the update apparently smooths out some of the bumps in the Australian 'Bathhurst track, and I personally preferred the game with the bumps!
Backup you original game files, just the files the NoCD crack overwrites, then try every crack there is. If none of these work then just replace your original files again and use your original disc to play.