The crane issue is common, I had problems as well, I had to adjusted it a bunch of times, since it's down I'm not sure if it's fixed completely, but if it's picking up and dropping off then most likely it just needs to be adjusted. In any case if you do buy a new crane make sure it's a new one because chances are the used one may be worn too. BTW, the crane adjustment is a allan key screw on the body of the crane (the hole near the crane cab)..the sweet spot is not letting the crane stay too long at near the end...in other words it should travel come to a stop for maybe 1.5 second then make it's way back toward the drop off...I noticed mine was taking 2.5 seconds to do the swing back and then it would stop short of the drop off. GL
Added over 4 years ago:
The fix for the crane was rebuilding the power supply....believe it or not, the caps get old and the crane slows down and the software will then release the ball before the crane docks, thinking the crane is broken. I changed the cap and the crane worked 100%
Added over 4 years ago:
Sorry I meant to say I changed the power supply bridge rectifier DB1....