Well, assuming the indication in the splash screen is accurate, there may
well be a corrupt file in the My Themes folder.
Quit PPT then navigate in Finder to:
UserName/Library/Application Support/Microsoft/Office/User Templates
Remove (or rename) the My Templates folder, then launch PPT. The program
will create a new one on launch. If that works you can start adding items
from the old folder back to the new one. Add them back one or two at a time
& re-launch PPT after each addition. That will enable you to determine which
file is responsible for the problem.
HTH |:>)
Bob Jones
[MVP] Office:Mac