The first two are easy: Poser can't find the necessary geometry files for something. The trackline has to be 100% accurate because Poser can be pretty stupid about things otherwise. The "out of memory" message is Poser's one-size-fits-all error message. It can't do something, so it goes into a snit, blames you, and shuts down, taking your work with it. The problem, again, is usually in the location of geometry files, so next time you get these messages, note what the track should be, repair the problem, and start over.