I've found that you need to have a positive integer at the end of the MOV line for weapons/objects to display. Blank or 0 is empty handed.
Here''s what I remember off the top of my head. Also, note that some MOV commands automagically put the weapons in-hand, like most of the "ENC or ENCOUNTER with CUSTOMsomethingorother"
1 - broadsword, mace, hammer
2 - katana, bow
6 - assault rifle
8 - claws
9 - dual blades/pistols
This does require that the MOV command also be compatible to some degree with the weapon. Although, you can mix and match. Like I've used the COSTUME ZOOMED command for SWORD, but added an "8" at the end to get claws to show up.
I'm at work right now, so my memory might be faulty, but this should help. If nothing else, experimenting with the numbers should help.
Harrison