If we're still talking about films where the UHD ISO plays fine but the MKV has dropouts, you can add The Martian Extended Edition to the list. This is another movie with seamless branching and Dolby Atmos. The dropouts in the Extended version happen exactly when there is a switch from an .m2ts to another one. As is usual with these films, no issue when an audio track other than Atmos is selected. And of course the ISO plays just fine. I tried MakeMKV, I tried using ffmpeg.exe to convert the .m2ts segments into .mkv then combining them with mkvmerge.exe, and I evaluated CloneBD hoping it would succeed where others failed, but unfortunately it seems there is no way to play this film in 4K with Atmos using an MKV container without dropouts. I use Plex for my collection, but for this one I have to use KODI and play the ISO until a solution is found.