Hi,
As an update for those who don't use pptview daily (as I do), built-in gdiplus is able to render most presentations that native can render. (By native I mean native gdiplus in wine, not pptview.exe in windows.) In fact, I cannot at the moment find a presentation that native can render but built-in cannot (whereas I can find cases to the contrary, pending today's patches). So it would be helpful if people could start using built-in gdiplus for their favorite gdiplus-dependent programs and reporting bugs.
Native gdiplus looks better (and probably always will, since it can do its own rendering, whereas the built-in implementation relies on gdi and the underlying drivers), but built-in should be faster. Also if you are going to try to use pptview in wine with either native or built-in gdiplus, I would start with simple presentations and work up, rather than starting with a 50-page real-world presentation.