I just finished it as well (with Jeff watching over my shoulder telling me how much I suck at Lugaru, thats what 4 months vs the entire existence of the game in any form does).
Superb campaign. Loads of fun. The part where you fill the role of all three characters is great and as Jeff said the part where your teamates kill the wolves off screen was awesome. The ice cave was awesome, although very hard to see what was going on at times. The ability to wall jump back up is great, I did it once, but died about half a second before killing the last wolf (I just had to touch him and he woulda died) . One thing I would say to make the ice cave a little better is to put an opaque floor beneath the translucent (icy) floor.
Also Shan's texture doesn't show up quite right on my computer, and Jeff told me he had the same problem.
I withdrawl my problems with "Ruins Top," I just found another method that was reallllly hard, but possible.
I never found the sideways trees Zantalos mentioned, but that's okay.
Now that I'm done pointing out some things I think could use slight improvements I am going to return to complements (the good-bad-good sandwhich of any good critic). The way you pushed the engine to its limit rocks. You used so many aspects of the engine to their full potential, from collosus structures to a different sword. I know that Lugaru as a wolfire product is considered complete, but I think you and David should work out a way to change the menu system (I think that is all which would have to be changed) to incorperate both campaigns in the package which comes with the game.