Hi @xi57 time has passed and I am currently on 5.2 preview2. As you said in this version CommonUIActionRouterBase.h has changed and the parameter ActiveInputConfig has been moved to protected:
https://github.com/EpicGames/UnrealEngine/commit/2b34c8ce154011a327087ee7e83fdbb6dacd7907
Also looking at the file the ApplyUIInputConfig is now virtual. So regarding the topic of this thread what should I do to change the behaviour of ApplyUIInputConfig without compiling all the engine. Normally I override the classes and then I use this classes as base for blueprints, but how do i tell the engine to use my custom ApplyUIInputConfig?