Your Resource.CFG also needs to have this text somewhere at the top in order for it to recognize the Overrides folder:
Priority 1000
PackedFile "Overrides/*.package"
PackedFile "Overrides/*/*.package"
PackedFile "Overrides/*/*/*.package"
PackedFile "Overrides/*/*/*/*.package"
PackedFile "Overrides/*/*/*/*/*.package"
In order to check if it is there and you have the correct file, you will have to right click on the Resource.cfg file and open it in a Text Editor like Notepad. The lines should be at the top of the file.
You also don't need to put hiders in an overrides folder, by the way. Some people just place mods there for sake of separation.