What happens is, after maybe 5 - 10 minutes, suddenly I see the red hourglass spinning (it keeps spinning, without stopping) and I am unable to select the person atoms. And also other atoms in the scene become unselectable. When I try to go into the select menu, it will not display them either on the list, (and I didn't mark them as invisible). I think it may be a result of a session /scene/person plugin I'm using, but I don't know which one... (I use a lot of plugins and some are experimental) I may have to just hard reset and figure this one out.