Hey Alejandro! By some unknown reason, your mail was recognized as spam, so we didn’t see it.
We can’t do anything on our side to solve your issues with nativization. The issue that you had with regular header include after generated header include means that it’s a bug in their nativization system, because in regular C++ programming for UE4 it’s also restricted. And Epic Games developers know that for sure. So it would be better to write bug report on unreal answers portal, but please do not include any part of UTC in your public thread with Epic Games, because it violates marketplace rules.