This appears to be a bug with the following versions:
B-3 V2 2.4.0.1552
Analog Lab V 5.3.0.1552
If I press a key and engage sustain pedal, then let go of the key and press it again while continuing to hold the sustain pedal, the note stops sounding. It doesn't keep sounding the note I press (which would be expected). It doesn't play two instances at once or retrigger (which would be annoying but acceptable). It just stops, and the note won't sound again until the sustain pedal is lifted. When the sustain pedal is lifted, an audible click or pop can be heard at the pitch of the note or notes that stopped sounding if pressed twice.
Also, one quick note: Arturia decided to reserve CC #64 for holding notes, which you can't even do on a normal Hammond. Sustain ought to be assignable to something gigging organists would use, like Leslie motor speed. If sustain isn't going to hold notes properly, as is currently the case, then why did they do it? I would like to hear from somebody on the B-3 V dev team about why it has to be dedicated to hold and can't be assignable to hold OR other things.