Got most of the stuff for import working so far. Export still needs some work.
Encountered some issues with missing functionality in the blender python api in order to complete this:
can not set the 'type' of custom node sockets thus they always default to 'VALUE' which causes e.g. ColorSockets to provide only the red channel as output
Got most of the stuff for import working so far. Export still needs some work. Encountered some issues with missing functionality in the blender python api in order to complete this: