help with CSM + 2005 MP

i installed the MP2005 but it wont let me open CSM with out this error message so cant install other mods

Duplicate GUIDS found!
you most likely copied a .csm file to use as a base for another subset or even another mod.
That's ok, but you'll need to erase the UID key from teh newer .csm file to force CSM to generate a new one.
The files are:
C:\Program Files\Infogrames\Grand Prix 4\Gpsaves\Carsets\MP2005\MP2005.csm
C:\Program Files\Infogrames\Grand Prix 4\Gpsaves\Carsets\MP2005\MP2005_full.csm

can anyone help me and tell me which thing i should delete coz this is confusing

Cheers thanks in advance

reinstall gp4, and then reinstall csm, and reinstall the mod, make it the first mod you install