Just to be clear, if I make that map_editor (in this case, for my game), and do not distribute that software (I only use it myself to create maps for the game), then I have to pay royalties because part of the game (the maps) would have been created in part by UE, correct?
That’s correct. It’s our hope that you have sufficient reason to just use UE4 across the board to make the game as good as it can be. At any rate though, since our monetization model is royalties, we try to be careful to not create loopholes whereby a game (or other software) can contain very material value created by UE4 but without a royalty obligation.