1. have you specified the object text font? Alternative method is to use narration text set as background & update it inside of a loop every x time passed. If it's a narration text you can force it to always display on a specific part of the viewport, unlike object text which I believe is fixed to wherever you choose to display it in the current scene.
Other alternative is to wait for when draw stuff that was added to 4.2.5 is working properly, then you should easily be able to have it automatically draw the score & update the score that's drawn each time the score is modified.
2. pause isn't really possible. The only thing that seems to pause the game is by switching to a menu scene & & using the keep scene in memory action thing. It's not really all that easy to pause a game properly as it would involve having to check all the active animations & locking them to their current frame values & various other things to disable scene interaction.
3. videos have to be mkv to be able to include multiple audio languages & subtitles. Don't ask me how though as I don't have a clue. Some of the other members on here have managed it, so see if you can find a thread on the forum somewhere about it...
Anyway, here's the wiki page David wrote about the video stuff: https://wiki.visionaire-tracker.net/wiki/Video_Encoding