The unit finally burped to life.
Strange it was dead on arrival. I'd charge it up 100%, then check it after 8 or more hours to make sure it's still at 100% (see if it holds a charge). I picked up a "dead" TP and it did the same thing when I got it (usb led flashing), then gave me a warning after a bit that it would charge faster if on the stock charger (it was plugged into my computer at work). At home it fired up after about 30 minutes and I updated it to CM10, then set it aside for about 10 days and it was still at 100% charge.
I had one with a bad battery and it would easily drop 2% in 24 hours and needed a new battery, not a fun DIY project.
I consider myself an advanced user, but some of what you say is a little foreign to me. Is there a site on the web that would take me through the update process? I got through the CM9 install OK, so I'm sure I could get through CM10 with a fee bumps...
Rootzwiki has the most info.
How to install jcsullins CM10 Unofficial Build 20121216, with Sound, Camera & Microphone, Updated 2/3/2013 - HP Touchpad - RootzWiki
Only if you're comfortable with a boot-loopin' TP, should you could try this:
Update to latest recovery (TWRP 2.41 via menu in
goo or flash
latest CMW6) and
latest moboot. Then make a backup in recovery (TWRP or CWM6). Then you can run Acme3 with an empty cminstall folder. It should find a lot of errors, and can easily take 10 minutes to run. Then you can run it a second time to see if it finds any more. The risk it that it might hang and cause problems. Mine hung after 5-10 minutes, I tapped the power button and it continued.... a good day to wear brown pants.
If it fails to boot, you have a recovery you can restore (in theory)
.
If it's good, copy CM10 and the recommended gApps to cminstall and run Acme 3 again, using Roland's excellent guide.
Officially, they recommend acme uninstall, and reinstall via acme3.
You should also check out increasing your system folder:
How to guide for changing your system, data, and cache partition sizes to whatever you want. - HP Touchpad - RootzWiki
I've done this twice and have about 450 mb for system. Also did it the hard way once.
If you update to the latest moboot, your newer TWRP backups (/sdcard/TWRP/backups) will be on the sdcard in a new folder. Previously in a folder with a bunch of zeros and new ones in a unique number. You can move the old ones to the new folder via your computer via USB. Not sure if CWM backups (/sdcard/clockworkmod/backups) are also affected. (I prefer TWRP, which is touch based.)