Argh, the FastFetch operation was not added to the registered operations, I’m sure I tested that but I think I reverted some changes inbetween. I really need to write some automated integration tests for stuff like that.
It should be fixed with the latest commit (only the c++ code changed, not the python code)
Thank you very much. I hope I will find some more time to implement all the stuff I planned in the new year 
btw. It is not possible to keep the changes that are required for 4.6 in #if preprocessor blocks, because UBT is expecting the constructor macro to be the first statement in a class. so my repo is still only valid for versions lower than 4.6…