Maybe I'm not playing on the same difficulty level as you guys, but the engineer was not a big problem. Level 23 mage at the time. (I assume we are talking about the cursed abbey here???) (I play on normal by the way.) Also, i couldn't freeze engineer with level 4 freeze.
After he summoned his minions I ran out of the room. Took a couple of hits, but nothing big. (Probably could have used special move to make a better escape.) Then took out all his minions. Steel skellies with lightning, Liches with Meteorstrike (sp?)
Then it was just a matter of keeping a distance and Meteor striking Engineer. It was a bit of the oll' pauze/run/minor restoration (I think 3 potions of) but then he was down.
