So... Poser still seems to want to treat the Public Documents runtime as the default. Turning it off causes problems with loading figures. The Poser 11.2.289 installer let me install to a new Poser 11 Content folder on a different drive, but that installer only has a small fraction of the content and it seems to be 3rd party stuff. I used the Support Files installer to get that content, but it seems to regard the Public Documents runtime as the default and doesn't allow me to choose another location. That's kind of annoying, as I would like to lighten up my main drive by getting all that content off it. I guess I can try moving that runtime to the secondary drive and adding it as a separate library.