If I understand you right; you can't do what you want to do. You can create a socketed LG in the editor, but the game doesn't allow you to put LG's on quivers. Except for the gem of ease, you can only put LG's on rings and amulets. If you do add the gem of ease to a weapon, you can only put one on it; so if you made a weapon with 3 sockets, the other two would have to be regular gems.
Sadly too, the game doesn't consider the quiver a weapon, so you can only put regular gems on it (though you can use modded gems)
Sadly too, the game doesn't consider the quiver a weapon, so you can only put regular gems on it (though you can use modded gems)