I won't get into a "my transmission's better" arguement, but I'll suggest that there may be more T20 transmissions in use right now than all the other styles combined. I don't have any stats to back it up, but I'd be very surprised if it weren't true. With all that use and some of it not-so-gentle, you're bound to find the weak spots.
I've had to straighten out bands and so far haven't had any problems, LD. I can't be sure why it isn't going into forward- are you shifting it at the spool, or with the shifter? Will it go into neutral and reverse? Is it just one side, or both?
Stuck in the seventies- not in the swamp.
(6) Attex, a Hustler, a Super Swamp Fox, (2) Tricarts, (3) Tri-sports, a Sno-co trike, 3 Dunecycles, and a Starcraft! ...so far