Yeah it works fine as long as you run the bat file once you install the patch to remove the starforce encryption.
I started reading this thread at no grip and after the first post looked for the no cd patch as indicated but could not find it so i googled. Should have read more it was mentioned later in that thread at post number 47.
http://www.nogripracing.com/forum/showthread.php?
t=186595&page=3
About the car classes system you mentioned..
I've not looked into the filing system as yet but methinks it might be pretty easy as it's what i did for SCGT. Maybe the same process will work. In that game also modded quite a bit when i bought it they had added a file called "patch" to which the main file of an add on car was added. With so many add ons some good some bad you could be racing against almost anything so the answer was to create a new executable. Only one or two had cracked how to copy and what to edit in the original exe and to be honest they had done a pretty poor job of it then deserted the game for the newer sims that had come about. I looked into it and came up with the answers and hosted a dummy called easy.exe with instructions which meant from then on each new carset made had it's own exe with 4 classes in it and anyone could put any car in any exe in whatever class they chose.
Still used today though the following of SCGT is almost extint nowadays see:
http://www.racecarsim.com/rcs_page_scgt_help.htm
As to online racing I think it'll be a while yet right now i'm learning how to drive all over again especially with my wheel as i've spent perhaps no more than a couple of hours in 5 minuite stints over the past 5 year on gran turismo. Me snooker has got lots better though
