Just for fun.. I'll attach a 750GB (desktop) drive to a RioCar here, and run the builder on it..
Bigdisk builder v4 ran okay. Now installing the player software..
EDIT: Note that this is a 750GB Hitachi desktop drive, with a SATA interface. I've hooked it up through a SATA-to-PATA converter board from DealExtreme.Okay, v3alpha11 installed, some tunes uploaded to the player, and now it's playing them..
Dunno how it will behave when that drive gets more full, but basic functionality works without any special fiddling.

Cheers