I also had to deal with one bitch of a kiln this past week. It made me feel frustrated, stupid, and incapable. I took many pictures and sent them to a college friend, Jared Ward who is trying to take a look at it for me. I did try a few things after talking to another friend whom formerly fired this kiln many times. I vacuumed out the whole thing and stacked the load more open in the bottom. Today I took another go at a cone 10 firing only to be disappointed. The kiln fired uneven again, surprise, with 10 flat on bottom & 9 bending on top. Yep. Fantastical. I refuse to attempt to fire my own work in this beast until it's even! Anytime I close the damper even a little there's SO MUCH reduction, like flames shooting out the kiln. Same thing happens with increasing the air. It hates me. Period.
Pictured above is my crappy ass pyrometer that doesn't work even a bit. Guess I'll have to call in the professionals to check out this thing.