DHTML Tooltip v1.2

I'm not really sure if this is a bug or not, but on the demo page, found above, the script works in FF 1.04 just fine, however, after downloading the zip file and extracting it into its own folder, then viewing the demo.html with FF-- only 2 (top and left examples) out of them all work.

Is there a reason for this? Or have I done something wrong.