I mean, i do everything, in geurilla then save it in the C:\Program Files (x86)\Microsoft Games\Halo Custom Edition\tags\item collections\single weapons, but it dosn't register under netgame equipment. And when i try to just insert .weapon tags, they are unusable when i play in the compiled map, and disappear in about a minute

One way to get your weapon in your map is to create a .item_collection tag for it. In Sapien, go to Netgame equipment and then switch to the game view -> right click to create a copy of an existing item on the map. Finally, you go to the property view and switch out the item collection tag for your desired weapon/item_collection.