A few suggestions:
When you save the file save it in PPt 97-2003 format rather than the default
PPTX - in fact, use Save As *first* to do so rather than getting started &
using Save As later. Many of the features available in 2008 are not
supported in earlier versions so they will get changed/stripped if you do.
Saving in the earlier format will force you into Compatibility Mode & such
features won't be available,
Use standard image file formats for any graphics & Insert them rather than
paste, and
Use conventional fonts available on both Mac & PC.
I'm sure some other ideas will be offered as well.
