First squad sent out by the assembly station worked like a charm, but the next squad that got sent out got lost in my labyrinth of transport belts and got stuck in the middle of my factory and the squad was pulled apart by the transport belts.

After picking them up and deploying them outside my factory they worked well, so I guess the pathfinding had some trouble.

I noticed that they seem to become disoriented very quickly when they try to pass over an express transport belt. Instead of driving on, they seem to stop on the belt.

If it's any help, here's the savegame: https://cloud.hamburg.freifunk.net/f/7926478eb4/?dl=1

Yeah the ai is the same as a biter, it can't handle being moved by transport belts very well. Always deploy droids at your walls or just outside. Guard station droids can be inside the walls but still try to keep away from spaghetti