Please help - Possibly bricked tablet

[Conker2015]

I have a 16GB JXD S7800b, and I decided to add custom firmware to it, mainly to fix the tiny program storage space, but also to increase the CPU speed. Anyway, I first rooted it (using the method in http/boards.dingoonity.org/jxd-devices/how-to-root-jxd-s7800b/) and it worked great. I then followed the instructions for adding new firmware (in http/boards.dingoonity.org/jxd-devices/s7800b-1-6ghz-(tweaked-vsync-fix)-minimal-rom-wother-fixes-(by-webclaw)/ using the file "webclaw-tw116-9-VSYNC(6GB).zip" from http/boards.dingoonity.org/jxd-devices/s7800b-1-6ghz-%28tweaked-vsync-fix%29-minimal-rom-wother-fixes-%28by-webclaw%29/msg116756/#msg116756 as the original file links are now dead) and did everything as instructed, and the JXD S7800s reset as normal, and came up with a message about formatting data, but then when it reset the tablet stuck on it's boot screen (black screen with a silver "JXD" in the centre).

Now, when I turn it on, all get is that boot screen, and nothing else happens at all. And I can't turn it off via the power button, only via inserting a pin into the reset hole.

Is there anything I can do about this, or is it permanently dead? And I know that if it is beyond recovery then it's my own responsibility, I know that these things always carry some risk, and I accept that, but what did go wrong in this instance? Did I use the wrong file, was the firmware that I was overwriting too new and so the over-write failed, or what?

Thanks for any answers.

 

[Titillating]

You may have better luck posting to that forum directly, if you haven't already. It's a pretty niche device that I'm guessing is only available in certain regions, and it seems as if the folks on that forum are the ones developing and releasing those ROMs. Always better to get an answer straight from the source.