I had previously posted a few times (here) about a little model train control application I put together with Nodered, ESP8266, MQTT and a PI4.
I recently "finished" an additional function to control a Marklin crane 7051. As with the other types of accessories, it simply plugs into a custom board instead of the original controller. This saves a lot of wiring.
It covers the basic control functions: lift up/down, turn clockwise/anti-clockwise, light on/off.
I also added a sequence function which moves the crane automatically using a the information contained in file. This can be changed from the dashboard.
I made a small youtube video about this which can be found here.