When I try to give the summon a potion, the engine makes me drink it instead. Which raises a small problem when I try to test out a poison on said summon.
This was you, not the engine. I drag potions over the summon all the time and they use them fine. Often, as in, nearly every single time I log in. You should likely use the allied boxes on the right to drag potions however, less change of an opps.
That's what I did, dragged the potion to the allied box.
hm, this does sound like it would be a problem localized to yourself. I'm forever giving potions to my summons and I've yet to bug out and drink them myself.
No. It could be easily be linked to the poison script that was never taken into account.