So I installed NMM, and here we go, it wants the custom ini. Game version is 1.4.
I uninstalled NMM and the game, then reinstalled it from steam and installed NMM again. Then I start the game the first time using the Steam Launcher, it said it is detecting video. NMM still wants the custom ini.
I launched the game, changed some settings, started a new game, made a save and then quitted. NMM still wants the custom ini.
I double checked ingame and launcher settings, yes, they were saved, and no, the game saved them without creating the custom ini, I only have Fallout4Prefs and Fallout4 inis in my My games\Fallout4 folder.
Then I found this thread and manually created the custom ini. Finally NMM got what it wants. You know, since the game perfectly runs without that file, at least after version 1.4, maybe NMM should actually create it if it wants it so much?