Any resolution for the sensor issue? I bought 3 of these tablets (for kids) and seem to be having this issue with 2 of them. They wouldn't auto-rotate, so I ran the sensor test, and the accelerometer (as well as compass, etc.) is not detected on both of them. The other one works fine.
Oddly, I've tried flashing back to the marshmallow stock images I've found in this forum, and the problem is still there. None of the custom images I've tried work either.
I'm not sure for certain whether the sensors worked when I got the tablets, but it would seem odd that two of them would have the exact same hardware problem. So I assume there's an incompatibility between the sensor hardware and the images I'm flashing?
$ ./adb sideload "343410B1702K88V2.0.0B17（SD card software）.zip"
E:footer is wrong E:Signature verification failed Installation aborted.
This package is not ks package! Installation aborted.