Did you know, some of our GPL WordPress Theme created using TimThumb to generated better thumbnail for the WordPress Content. The scripts have some problem on some server. Such as this script need to have abilities to created / recreate some cache in our server. The other big problem is Readfile functions. On some server this server is disabled for security reason.
After we googling, I found the easy solution to fix Readfile problem. WP Tricks coverage this problem and how to fix it. So if you server have some problem about Readfile you can go to the site and began fix readfile on TimThumb and began edit your current TimThumb to make it work.