After getting hacked bigtime, I engaged a security company to clean my sites and button down my hosting account.  Happily, all is secure.  Sadly, my thumbnails in Simple Image Gallery Pro have been replaced with blank boxes.  Has anyone else had this problem?  Does anyone have a solution?  I found another post with a similar problem... though not involving a security company... and a solution recommended by JW that revolved around cache file permissions.  I had my hosting service check that out and permissions seem in order.

Here is an example of the problem:
www.hiddenfairways.com/blueberry-plantation-photos.html

This is another of my clients, at another host, not yet secured, with SIGPro working fine:
www.laurelcountryclub.com/may-2011-photos.html

Help would be appreciated!  :(

Make sure that your thumbnail cache is writable.
In addition, please avoid using caps letters, dashes or any other special characters in the names of your pictures.