That's the same board I have, 1.0a, (stock firmware shows it as 1.0, I thought there would be an "a" afterwards, but there isn't), it flashed with no issues. All of the info is out there, it's just spread around. Basically, my process was:
a) Out of box, determine the it was a J37 board.
b) Jumper J37 and power on, wipes stock firmware.
c) Follow instructions Browning54213 linked to, also double-checked with video here: https://www.youtube.com/watch?v=rjuCvlnpB7M
d) Verified Repetier installation and used auto-level.
e) Loaded Repetier-Host program and got stuck for a bit, then found this video: https://www.youtube.com/watch?v=r7ztSYTACLo This video helped a lot and got me functional.
f) Did a test print that came out very stringy. Upped the temperature and started trying to print 20mm cube. Got a couple stringy / loose prints and found I had missed some settings in Slicer.
g) Put correct setting in slicer (extruder nozzle diameter and filament thickness) and printed an awesome 20mm cube.
It's pretty easy, I hope the printer is reliable!