Oh that sounds awesome, sounds like its going well and I hope the final pieces work out. Sounds like you're making a much more complete suite than what I was planning. I was exploring browser based flashing recently just for fun.
And your reasoning for re writing the flasher from scratch is pretty similar to mine (although I had the added goals of micro controller compatibility and getting rid of any relationship to Windows.)
And yeah it is a bummer, I've been enjoying this project (at least, since I stopped posting about it...) but I really can't justify owning the car any more, too expensive to keep fixing and not reliable enough as my only daily driver.