The basic problem is that PS is pretty slow for everyone, even people with impossibly good hardware. Hopefully the situation will improve somewhat with the next release, but this *alpha* software, i.e. they\'re more concerned with testing out and adding features than working on polish and speed.
Speed *is* a concern for the crystal space team, and work continues to be done there, but the developers are spread pretty thin when it comes to maintaining and developing an engine like CrystalSpace