I did the short circuit method too in my Onda VX858 emulator and it work fine as usual.
The only problem was that I spoiled a bit back cover... anyway I enjoy playing with my player not looking the nice manufacture
What I found inside was all of unknown manufacture... the only know chips beside Rockchip, were Samsung, a couple of them (flash and bios keeper) it took me some time to discover which Samsung I had to short circuit.
It get locked because I install VX858LE just to know if it can work... Geez... finally my player is VX858 V1 as V2 firmware works pretty bad in my device.
Recently I learned to play with my VX858 when is charging the battery via USB port.... anybody knows how this is called?. I mean to have the player USB plugged while the user is playing music or whatever.