I found instructions on Infinity Tools website and for Amana. I got the bit working today. At first I rearranged the cutters so I had two of the little cutters and the big one on top. I got it to work but had a lip at top and bottom. I figured out that I needed three of the cutters and the large one and the problem was solved. You would have to rearrange the cutters for your particular thickness of wood. I had 7/8" thick. The cutter is a little picky but once I got it dialed in it went like clockwork. I used my coping sled that is usually used with cope and stick router bits. The coping sled held each piece very well and I got the height all set up and replaced the backer board and go no tearout or fuzzies. So far so good. Like many bits, 45 degree lock miter, and others, there is a lot of fussy setup. Once you get it set up things work well. It is just frustrating to get to the perfect setup.
One thing I did learn is you run one end, part A through the router, then you run the second board, part B, and place the A cut on the table and turn the B cut over and slide the two together. If part B is above part A then you move the bit down. If the opposite is true then you move the bit up. I have a Jessum FX router lift and the crank is calibrated to 164" increments.