Are you with Tibia 10 or Tibia 11? Because it may act a bit weird with Tibia 11.
For it not to heal, it should be probably connection issues, as I'm using both actions and the healer so if one fails the other will work.
For it not to use UE, then you need to adjust the health range a bit more. If it's using randomly, then I got no idea.
For it to take your necklace, either you started the script without it (and then it recognizes the main necklace as 0) or the script got a bit confused . I will change the method and write to the database instead of checking it every load.