BluRay re-authoring help needed

I apologize if somebody asked this before, but I wasn't able to find something similar.

I have bought the remastered Star Trek BluRays. The problem is that they don't have the Czech dub. I have the Czech audio recorded from the TV broadcast and I have synchronized them correctly to the video.

I want to take the official BDs, remove the German audio track, replace them with the new Czech audio track, and make a new BluRay disc which will have the same menus, same bonus features, but it will play the new Czech audio instead of the German audio .

I know how to do it with DVDs, I know how to do it with mkv files, but I have absolutely no idea how to do it with BluRay discs. Any tips ?

I want to do the same thing with the Clone Wars BluRays, but I want to add subtitles there, is it a different case ?

Thanks for any help

Thanks, I'll try it

Is the software "clean" ? AVG claims there is a virus in the exe file and I downloaded it both from VideoHelp and from rapidshare (link on official web)

And will it allow me to keep the original menus ? It doesn't look like that from the tutorials on the website