Because the EP-68 rarely has a working "Reset button" for loader mode, you must use Mask ROM Mode:
: To get the PC to recognize the device, you must often press and hold a hidden recovery button (usually located inside the AV jack) while plugging in the power or USB cable. Rk3128 Mxq Ep 68 Firmware
The first boot after flashing takes (Android is rebuilding the Dalvik cache). Be patient. Because the EP-68 rarely has a working "Reset