very much not so much beta, but check twice before using!
There are tons of fancy hacks for catching rewrite behavior of apache. As you see, it highly uses variables for deciding to rewriting and there must be many much errors/unmatched directives.
Q: Does it supports xxx?
A: This page has woozy codes, I dont know try it yourself and see. Backreferances, most of the variables and a few flags are supported.
Q: Will you make the codes public?
I think no, because I dont want to feel ashamed, I am tidying the code now, but if you want to have/see codes immediately you can email me (anil?saog.net), I will send this code crowd immediately.