thermometer.php and wxgraphs not working since migrated to Mac.

Hi all,
ive successfully migrated weather display and my website to a mac. Everything is working fine apart from the thermometer.php image and all the wxgraph images.

All the files seem to be there ( I really just copied my entire webfiles directory across).

Any suggestions of where I could look?
Thanks :-()

A link to your site would really help.

what files do those use?