Software

It should say DocName.ppt (Compatibility Mode) across the window title bar.

Microsoft PowerPoint 2007 & OpenType CFF Fonts

Microsoft has been hard at work fixing a couple of bugs Windows PowerPoint 2007 has in working with OpenType CFF ("PostScript" flavored OpenType) fonts.

The first is pretty serious. Set text above 64 point in an OpenType CFF font, and it all munges together, overlapping. It's basically unreadable and unusable at these sizes.

The second is a little more subtle. Apply underlining to an OpenType CFF font, and the underline will be shifted up slightly, above the baseline instead of below, so it cuts into the text, almost like a really low strikethrough. Now, as a typographer I don't use underlining all that often... except for URLs, which show up in my presentations all the time.

The latest Windows PowerPoint hotfix fixes these issues, hurrah! However, it has not yet been rolled up into a regular update, because it has not been as fully tested as everyone would like. It definitely solves the problems noted above. If you are encountering these problems and need them fixed *now* and are willing to take a slight chance, then you should download the hotfix. To get the fix now, rather than waiting, you can request Hotfix SRZ071022000448.
http://support.microsoft.com/search/?adv=1
[added info 17 Mar 2008:Microsoft's writeup is now available in their Knowledgebase article 948941.] Otherwise, you should wait for this to be rolled into a regular update (available through the Microsoft Update service), or a later Service Pack update.

Please post back if you have any more problems or questions.

I had the exact same problem, and found a reference on the PPTools Site www.pptfaq.com)
to bat printer drivers. I deleted my default printer, and selected another printer. My slide then loaded perfectly.
Hope this works for you.
Don