I see what you mean. I couldn't find anything in the settings to make it full screen, even when rotated to landscape mode.
enTourage I believe has done in-house testing of VGA adapters, and most likely with Powerpoint (what else would you want to project, lol?), so feel free to email
techsupport@entourageedge.com to see how they handled this.
Or, maybe there's another forum member that has solved this.