Harmy I already talked about chapter branching here as I'd love to make an "international" Blu-ray (with available foreign crawls). I just discovered you can do that with mkv files. Would you be ok for me to try and make such a file if I can find out how ? Apparently there's a software that does that but it hasn't been updated since 2011 and it crashes on my Win 8.1 install. Will try on a Windows 7 VM (if you're OK with that of course).

If you are OK with that, please tell me, I will create a separate thread for my project based on yours.

Good luck with the build, btw!