This final release worked like a charm for me: I copied the qdsopts.txt, the new omnicron/pak0.pak, and deleted the quakeds.sav.
This release appeared to fix the problem of resetting the attack binding.
Bring on RailArena!
FWIW, I'm running this on M3 Simply DS with the latest firmware. I don't even have to patch the DLDI thanks to the autopatching.