I noticed that this place seems to be a common prob for ppl and decided to offer a bit of advice...
First off many fights are ez if u use this tactic, it's cheap but it works. Have your guys stand well away from the door with all their helpfull spells on them. Then summon a few of your favorite creatures and then haste all of your guys including the creatures. Walk a summon creature and a party member up to the door open it and run leaving your creature there untill a few of the bad guys chase it. Kill thoes then rinse lather and repeat as necessary. ;)

nice, now let me butt in :D , cast chaotic commands on a fast attacker (preferably with boots of speed and dual wield, and low AC), go in and smack them all!

Barloc, dont forget High Int. otherwise the first hit will kill them. My personal favorite is.
Also, haste is better than boots of speed for dual weilders. I did a test once, and haste gives +1 attack for dual weilders, boots of speed gives +1/2 for everyone, but they wont add up, so once you get the +1/2 from the boots, haste doents give any more attacks.

yea, the potions are very important, but i had 12 strength and low ac and was able to get hit only twice