If you are just copying the files out of the achive and dumping them into the game folder, then, you are loosing the folder structure that you would normally receive if you "extracted" the archive. This folder structure (path/file names) is contained inside a lot of the GTR2 files. If the track attempts to load and it can't find the file it needs based on the folder structure, then the track will not load - period.
I suggest you use the archive "extract" option and either place the files in the location identified in the enclosed "readme" or, place the files in a temporary location and then copy them (with their folders) to the appropriate locations in your game folder.
I do the latter and it has never failed me (except when the 'creator" messed up). It also allows me to view the file structure in case aI need to make changes for my specific intallation.
Hope this helps.............