I noticed that upon using the Office Viewer Macro on pages with a dash in the name (such as "M-16") with ppt attachments no images are displayed. Renaming the page to something without dashes (such as "M 16") it works flawlessly, again. I figure the problem is that the image URLs include %2D instead of the dash in the filename part. In aboves example this would look something like this: "/bin/temp/Space/M%2D16/officepreview/Space.attachment.ppt/attachment-slide1.jpg"
Interestingly enough, it works on pages with non-ANSI chars (such as Ä, Ö, Ü, ä, ö, ü).