The way I create cross-platform CDs is like the following: using Toast for a Mac, select "custom hybrid" in some versions of Toast or "Mac & PC" in newer versions. For the Mac side, point Toast to a Mac disk image. This will require you to create a DMG file with your Mac disk utility and then dropping your slide show files into this image. You point Toast to the mounted disk image (not the dmg file). For the PC side, you just drop the "files and folders" into the "files and folders" area. When you burn this hybrid CD, you'll get a cross platform disk that loads the Mac image on a Mac and the PC files and folders on a PC.
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