I've always found loose pack to mean no sealed packaging so may need re-oiling etc and the others come sealed in packaging to preserve the lubricant, I've had a couple of loose pack movements and they have always arrived complete and working although sometimes without hour wheel, never had one sent in bits,
What movements did they send you in bits seikochrono? I'd like to steer clear of those if I can .
all the best
AKA: open box....lolTaken from Cousins front page in the "Movement search by make and calibre" section
Loose Pack = Exactly the same as sealed except originally destined to be fitted to watches for retail but are surplus to requirement.
The information is out there if you look!