go to the blog.gib.me/ and download the XLive Wrapper and copy the CopyXLiveResources.exe and the xlive.dll into the GTA-DIRECTORY start the CopyXLiveResources.exe and klick Okay.
then work the trainer.
Why just some people do have problems with this thing?
Is it because of OS version?
I installed the game today on Vista Ultimate and Trainer works just like a watch.