I think there's an OS glitch with patch ROMB-67 (MWQuant BC) where the mod wheel destinations read "-reserved(73)-" and "reserved(74)-" from the front panel, and show as blank destinations when viewed from the plug-in - but they still work. Does anyone (Ben?) know what they're controlling? I'm going to try and figure it out, but thought I would ask/report the bug in the meantime. I'm on 5.something, can be more precise if required.
Cheers.