Crackproblem with Gothic2+ADDON

[Low]

i copied the three fixed exes from souldrinker (ar.exe, spacer2.exe, gothic2.exe) into the system folder but if i want to start the game with the burned cd only a black screen appears where i only can move the mouse but nothing else happens. so ive started it in windowmode. there was an errormessage (couldnt find default.tga). at the end ive replaced the cracked exes with the original ones but the same screen appeared when i started it with the original cd. the strange thing is: before copying the crack the game ran normally.
Who can help me???