Help - With drop gun script

I use this script [Release] DropGun [1.0] in test server everything its fine works perfect, but when i put from test server in my main server he stop work. When i write /drop he put gun on the ground but this gun always disappear, and i see in test server police npc drops gun, maybe i need something turn on in my main server?

Somebody can help me with this problem?

Ask on that scripts forum post.