ANTRIEBRELAIS FREISPIELZAHLWERK = PROPELLING RELAY FREE NUMBER OF CYCLES WORK

Actuator relay Free game counter
= credit relay by the sound of it

NULLRUCKLAUFRELAIS = ZERO JERK RUN RELAY (  No its not the tilt)

Hmmm, zero flip current relay??? Maybe something to do with disabling the flippers at end of game? Has to be activated to allow the flippers to operate?

RELAIS PARALLEL MIT HUNDERTERZAHLWERK = WITH HUNDRED NUMBER HUNDRED (  100X 100??)

Parallel relay with hundreds counter

EINER TONGERAT = FOR ONE CLAY TURNOUT   

sound generator?

Hopefully those guesses help a bit...