How to install tracks
David Greene
. GP2 stores the circuit data as files called F1CT01.DAT - Interlagos, 
 F1CT02.DAT - Aida etc.. These files are usually only stored on the CDROM and are 
 not copied during a full install. They are in the GP2/CIRCUITS directory on the CD. 

 2. To use tracks you will need to get a patch that modifies GP2.EXE so it will 
 read the tracks from the local HD instead of the CD. This is usually the 
 GP2NOCD.EXE program. 

 3. Now you need to make the CIRCUITS directory off your main GP2 directory and 
 copy all the DAT files from the CD. Its worth noting that there is a 200mb file 
 called TRACKDAT.BIN that is in the same directory. Its a bogus file and is not 
 used, so dont copy it,  just copy the *.DAT files. 

 4. Once you have done this you are pretty much set.. Now all you have to do is 
 install the new track by copying it into your newly created circuit directory 
 and deleting the circuit you wish to replace (you can copy it back from the CD) 
 and renaming the new track to the correct filename eg. F1CT01.DAT to replace 

You can't add tracks you can only replace existing ones. 
 Make sure you have done a large install. 
So if you only have done a small or  medium install, you need to reinstall GP2. 

 I hope this was clear enough for you.