With the evolution of the guider setup logic, including making the preview images for the web display, it turns out that refactoring SetupGuider to simply save the full frame guider image as FITS and then PNG, attaching the FITS to the PinPoint Plate, etc. will simplify and streamline it. Plus it avoids the evoils of Camera.GuiderArray.
This came about from these MaxIm tickets (and associated cross-linked Comm Center tickets):
UNDO THIS, GO BACK TO Camera.GuiderArray.
The process of enumerating the documents looking for the AG window, then saving out to disk, etc. caused other problems (see related tickets). Daniel VanNord of Optec says getting the Camera.ImageArray is good, and I never had problems before the evil Midsummer's Nightmare of MaxIm 2015.