Well, the non-detergent requirement is to avoid "foam" buildup in there, and to ensure the quality/purity....some detergent additives might not be so nice for use in a moped tranny.
As for theft, just do a forum search for REPOST and you'll find a sheet of useful info to make very sure that puppy stays yours.
The four and five spoke jobbies are mag wheels, and quite easy to retrofit as long as you can get the sprockets and brakes to match up, and that's usually simple.
As for the operating temperature, I don't know offhand, but I don't think it'd go that high, Fred or Ron might know exacts on that, or not.
-R