Oh, didn't think about that. Multiplayer/ network instructions are only available in (the former Commercial and) the Pro edition, sorry. You will have to use a single window it seems (which I'd suggest anyway). Have a look at this feature as well though: http://www.conitec.net/beta/video_border.htm
"Falls das Resultat nicht einfach nur dermassen gut aussieht, sollten Sie nochmal von vorn anfangen..." - Manual
