The deeply colored version is what "Pure" is supposed to be, but if "gray" isn't getting you a more conventionally colored anaglyph something is wrong.
V11 wasn't written for vista but I doubt that's the trouble.
V11.0 was dropped pretty quickly for V11.1, but I'm not sure either one ran on the Yeti disk. My 11.1 runs on the Orangutang disk.
different thing to try:
-help>reset all
-uninstalling and reinstalling.
-try v11.1, available on upgrade server.
as a workaround you could render to "cross-eye" and combine the separate images in Photoshop as you are accustomed to.