Recently bought the K8200, took a long time very carefully building it and double checking everything.
Very unhappy with this, things wrong are as follows:-
Z axis lead screw not straight
Z axis motor mount incorrect fit
Z axis micro switch does not line up with stop bar
X axis motor noisy
Print bed warpped
Controller stuck in test mode???
No comunication with software even though shows as connected!
What can be done please?
It would be helpful to have pictures of the problems where possible
The control board is the first issue that we need to address and any software issue. The lead screw and motor connector can be seen bent when moving.
The led on the board at LD2 is permanently on and the fan always on.
The led at D4 (heater 2) is flashing randomly
No led seen at the usb port when power is on.
Tried new software, problems are still there 
Please try to check the wiring to the control board carefully. Seems like one or more wires could be wrong connected.
Have done everything possible more than once, think the control board is faulty.
In that case please return the board for inspection/repair/exchange.
most inportant is de order you do things
1st connect print with pc with usb cable
start repetier
connect
en then you might plug printer power on
it should work
You can try pressing the reset button on the top right corner of the board after you pressed connect in Repetier.