1. Install VAS over the top of the unpacked mod following the 1st page of instructions at http://forums.bistudio.com/showthread.php?149077-Virtual-Ammobox-System-(VAS)
2. Edit file \fnc\interact\fn_interaction_else.fsm & replace path scripts\VAS\open.sqf" with the location of where you unpacked VAS.
Do it this way instead
"The only file you need to replace is [unpacked pbo root]\scripts\VAS\functions\fn_fetchCfg.sqf
Just replace it with one from the unedited VAS code." jeriktelorian