I have an Advantage II that I retrofitted with the ultragrate kit 3 months ago. Since then, I have had nothing but BAD performance. I cannot turn the auger past 2 without pellets building up and even on level 1, I have to stir the pellets around every few hours or they will build up in the grate. Also, there is a lot of black buildup in the box, on the window, and even the side of my house is now black. I have adjusted the damper from almost closed to ALL OF THE WAY OPEN, which is where it is now, and nothing seems to make a difference. I cleaned out the exhaust pipe at the time I did the retrofit including completely taking it OFF the stove and out of the wall to make sure it was very clean. Probably overkill, but I'm terrified of a chimney fire. Any ideas as to what the problem is? I thought this grate was supposed to make it burn better, but I'm very disappointed to say the least. I'm ready to throw the old grate back in and be done with it! The flame is not lazy and it's not hard to light. There seems to be enough air getting in to burn, but not enough to burn the way it used to. Thanks for any help!