I've had a few issues with this on two quests so far. Dragon slayer 1 it gets stuck once it collects the 3 map pieces, it kept on running back to the goblin in the cage (map piece goblin) and kept trying to talk to him and gets stuck in this loop. Is on the step where you will need to speak with "ned" to meet him at your boat to kill Elvarg. (close to the end).
It has also got stuck on Priest in Peril where it teleports to Varrock and gets stuck in the centre. Before the part where you deal with the "vampire" and throw the blessed water over the coffin.
I have had to complete these ones manually - not sure whats happening on these bits but its a little annoying having to babysit it in case it gets stuck