How to repair bricked UG802 Mini PC not booting

UG802 firmwares: http://www.arctablet.com/blog/forum/ug802-mini-pc/
http://www.arctablet.com/blog/category/devices/mini-pc/ug802/
Rockchip Batch Tool 1.5 tutorial: http://www.arctablet.com/blog/featured/flashing-arnova-g2-rockchip-2918-rockchip-flashing-tool/