You save a pose, exit the program come back another day, load the pose and no window appears but parameter dials show correct settings and it will actually render but still no window with render or preview in.

Double click on the window title.

and? that will bring it up?

Lemme see, as I understand it, you are trying to load a saved pz3 and when you do, the document display window is missing. Right? If so, go into the top drop down menu and try to manually set the document window size. If not, could you post a screenshot, as I'm not quite 100% sure of what you mean.

Set up the workspace as you want it, then save it by clicking on a UI dot. (If there is some other type of dot visible, select the UI dots with the drop down list next to them.) Then, whenever your interface gets messed up, you can click on the dot to recall your favoured set-up. I have two of these set up: one with a square workspace, and one with a rectangular landscape format.