Alright, so the bolt forward problem has been solved.
I found that the lpr piston o-ring had a "flap" on it, which allowed proper pressure with some shots, but when the "flap" opened up, was causing excessive drag and thus low lpr pressure.
However the board/battery issue remains. After only an couple hours, a fresh high quality battery goes from just over 9v to totally zapped.
The gun has a Tadao board in it - is this a common issue with them? I found some yellowish-orange crud (best I can describe it) in a few areas on the back of the board, but especially around the battery terminal solder joints. I carefully scraped away a good bit of it, cleaned the board with a q-tip dipped in alcohol and allowed the board to dry.
Powered up, shot great. Come back to the gun about 2 hours later and dead. Install fresh battery, it works. 2 hours later dead.
Any other ideas?