I've come up with a fairly foolproof drying method that I used here. I took the fresh burl and cut into slabs on the bandsaw. Then each slab was cut into pipe blanks. The pipe blanks are cut over sized to allow for warping and shrinkage. I noticed that this particular block shrank about 2mm in one direction, not too bad.
The wet blank is wrapped in paper towel and put into the microwave, set heat on lowest setting, microwave for a few minutes. Take the blank out and put under a bowl, the blank should be sizzling and steaming (if not, put back in), the paper towel will be moist. Let it cool for 5 minutes. Look at the amount of condensation on the inside of the bowl, then dry the bowl for next cool-down. After allowing to cool for 5 minutes, put back into the microwave for a few more minutes, repeat above steps. You know when it's done when you take the wood out and the paper towel is no longer moist, and there is less condensation on te inside of the bowl after cool-down. The wood will be warped slightly and feel dry. It takes about 15-20 minutes for a pipe blank to finish drying.
From what I gather, the microwave heats the lignin between the wood fibers so that the wood is able to shift without cracking. The paper towel covering allows the wood to stay in a humid environment while drying. Out of 5 pipe blanks, I noticed one minimal crack, about 4mm long, not bad.
So, here's how the pipe turned out a few hours later. I went with a padauk stem, and African Blackwood bowl insert. It's not perfect, this is my first time doing a "classic" shape.
No clue what went wrong, but I didnt wait 5 minutes between cycles. Thats probably what caused it.