So what I'm going to do in this thread is go through each line of the BetterRenkoBarsType and try to understand how it works. I'd appreciate it if experienced programmers could keep an eye on the thread and let me know if I'm going terribly astray. I hope that by working this out in public I help someone else, now or in the future.
If you want to follow the thread it will probably be good to have the BetterRenkoBarsType.cs file on your computer. You can download it here:
Special thanks obviously to aslan for designing BetterRenko bars and for making the code available here on Big Mike's. If it wasn't for forum participants and all their generous uploads and comments I would be even more ignorant than you will (very soon) realize I am.