At this time, Shopping Cart Creator has not been updated to support PHP 5. However, with just a small change to one of the included PHP files, you can make the shop function correctly. Here is what you need to do.
1. Locate the config.inc.php file in your shop folder.
2. Open that file in any editor.
3. Locate this line of text error_reporting(E_ALL ^ E_NOTICE);
4. Change that to error_reporting(E_ALL & ~E_NOTICE & ~E_STRICT);
5. Save the file.
Just remember that if you make changes to your shop, you will need to make this correction each time.
We are hoping to have an update in the next few months to address this issue and add other exciting new features.