So, pretty simple problem to describe, but I don't know what's causing it. In Poser 13 when I right-click the document window, in the subsequent pop-up there's no option to select between OpenGL and Sree3D. It's not that I can't change the option, it's just that they're not there at all. I've checked my preferences and such, tried opening different files, tried new ones, checked my settings, but the options are just not there. Any ideas?

Simple, it was taken out from the Poser 13 version.

Well, that would explain it.