As IKB said....
But, basically, if you want a specific 2006 (or even earlier) spec loco then just download it and see if it works (check in CM to see if has any faults/faulty dependancies). You can always delete it (or fix it) if it does not.
n.b. Loco specs changed from TC3 onwards (inc TS2009/10) so older assets may need some updating to work "perfectly" in these versions. Information about what needs changing (and how to fix errors) is available from various sources including the Trains Resources website newsletters.
Good luck!!