Ok, everything was fine... started up poser and now when I go to materials.. the document window is no longer showing up!

WHAT DO I DO?!

For starters, turn off Caps Lock.

Then, try this:

Window menu --> Show All Tools

Not sure about the document window. It may be hiding behind the material pane or Library panel (try moving them to see), or it could be offscreen. Double-clicking on the document window's title will hide the window itself, but I don't see the title itself anywhere in your screenshot. You might need to relaunch from a factory state to get it back, if you don't have the UI stored in your memory dots.