CSM is fine. its with the gp2 mod theres been a few problems, and hundreds of downloads.
i'm sure on some systems there could be problems, but what you describe is pretty generic so if it works on one it'll work on all.
try adding this:
fastwadcheck=0
under the [Settings] section in the file: 'C:\Program Files\CSM\Settings\Carset Manager.ini'
and remember 2 things - 1, the GP2 mod and the 05 beta should work fine with build 45. the only problem is your tracks will be wrong order (ad you'll miss out on 19 tracks in 05)
and b, the build 55 is 'unofficial' - i forced Zaz to let me have it, even though it might not be perfect
____
Tony