The mana restorer will be fixed in our next release.
It is a pretty tough script though, you died on floor 3? That's right when it starts getting crucial because of the behemoths.
I'll take another look at targeting and see if I can come up with any changes. Rydan has been running the script just fine but he's level 415-418.
Also, are you using garlic necklaces? They help quite a bit. In the next script update you can set a specific list of creatures to equip rings/amulets, wouldn't be a bad idea to equip a prismatic ring if 2+ behemoths and garlic necklaces on 1+ medusa / serpent spawn.