Nope, as far as I understand that is just the behavior you are going to get when testing the genericmod map override when testing in editor. Changes you want to test in the editor you test on the test map with it loading your new gamedata and testgamemode. Once you are past that you set up your genericmodmap, cook it, upload it (it doesn’t need to be public if this is the first version), subscribe to it, and test it in single player.