Thanks for your fast reply.
1). I'm stiil not clear, Bro. OpenLP just displays names when I add videos to Media Manager (eg. vid_001.mov, cross.rainbow.145, etc). There's no thumbnails, so I don't know what the content of vid_001.mov is. I think displaying thumbnails is more useful in this case, rather than names only. Is there any configuration I have to do, to make OpenLP displays thumbnails also, not only names?
2) Ah, so I can make slides just by clicking Insert button, ignoring verse order? Ok, thanks Bro. I'll try it.
3). I set my second screen to 800x600. So I have to choose pictures and videos in 4:3 ratio in order to be displayed fullscreen?