hmm very strange, if I try to run it with the Race 07 desktop shortcut which points to (C:\Games\Steam\Steam.exe -applaunch 8600) I get the popup, if I try to launch with the GTR-E shortcut (C:\Games\Steam\Steam.exe -applaunch 8660) or STCC shortcut (C:\Games\Steam\Steam.exe -applaunch 8690) it appears to run, I don't get the popup, Steam Friends shows me in-game (for a few seconds) but it never actually starts and the Race_07 process doesn't show in Task Manager.
I've just verified the integrity of all 3 installations and they were all OK.
l8r