Regarding inserting a monster, someone here suggested it to me. Or maybe I read it at the beginning of the thread by Ser9K...
2) Yes, I also save them that way. I used to just put them... I don't remember where anymore, but the point is that if they are inside the map after closing the editor, then it's unlikely that anything will happen to them. =)
RedHeavenHero - I definitely had that issue a couple of times, where the video is on the map, but it's not visible in the editor (neither in the dropdown list nor in the regular list of the extended version). Then I came up with inserting the video as a start scene in the properties tree of the map using a text editor, and then, already in the editor, I just did a refresh, after which it reappeared. I know, it's not a quick method, but it seems to work. =)