You can add an uniqueid to make it not moveable.
And the difference between the quest.lua and the system.lua is that the system.lua has alot more options.
In the quest.lua the uniqueid is for the storage and the itemid, so you can only add 1 item and you can't use the same item for an other chest.
Also if the uniqueid for the itemid is already used as storage for an other script, you can't use that item for the chest.
With the system.lua you can add all items you want, more items, stackable items, etc and you don't have a problem with the storage being the same as the itemid, so you can choose anything you want.
And the difference between the quest.lua and the system.lua is that the system.lua has alot more options.
In the quest.lua the uniqueid is for the storage and the itemid, so you can only add 1 item and you can't use the same item for an other chest.
Also if the uniqueid for the itemid is already used as storage for an other script, you can't use that item for the chest.
With the system.lua you can add all items you want, more items, stackable items, etc and you don't have a problem with the storage being the same as the itemid, so you can choose anything you want.