It comes up in German because the parameters are gone. Make sure the 3 AA batteries are good and that there is no corrosion in the battery holder. If there is corrosion, you may need to remove the control and make sure the leakage did not eat away anything on a board.
Press the CE button (clear error) and it should go to the parameter page ask ask for a value for the first parameter. You can enter the "sister" machine's parameters but be aware that some are machine specific. These are usually written onto the parameter sheet longhand. This includes backlash and travel limits for each axis from the home switch.
You cannot download your parameters because you probably do not have any. This may also explain why your spindle drive does not come on.
You can upload parameters by setting up the control in RS232 and the baud rate under the MOD key. You will need the correct cable and COMM software. Then press EXT and enter and they should go in.
BTW, I will be at my office in the morning, and I will see if I can email you that KTK drive stuff.