I found the "Styles" in the Program Data folder under VideoEffects. In the older version I have, these were in the Effects tab in the Media Pool area, but I can't find them at all in MEP 2013. Where are they supposed to be?
The files themselves are there in the "C:\ProgramData\MAGIX\Movie Edit Pro 2013 Plus\VideoEffects\Styles" folder. But they don't show up under the Effects tab. At least that's where I'd expect to see them.
That's what I was looking for, but it's quite a bit different than I was using them in MEP 11. I'll have to go now and read how to use the Slideshow Maker.