UPDATE:

The x264 conversion if finished, and the final video looks pretty good!

Now I should only mux all the soundtracks and subtitles files, but I have some problems to identify .sup files - to discover which file is which language, I'm muxing ALL soundtracks and subtitles together right now, and then when this test mux will be ready, I hope I'll find which is which...

The most challenging task will be to discover which commentary soundtrack is, as there are five of them! At least, I will mark each with english, and put them after the other languages.

Last thing: I discovered, with surprise, that there is a japanese soundtrack between the others... the fun fact is that is not listed anywhere, not in the cover neither in the BD audio menu...

I love it, but, even if I like almost everything about Japan, for this project I'll prefer to get the german soundtrack, as I promised myself to use five main languages for my projects if available (english, french, german, italian, spanish); and german is the only missing for "The Matrix"... if someone have it, and want to share, I'll be really grateful! And I bet there are many german speakers here who will really love to hear one of their preferred movies dubbed into their main language!