Upload:
Select "Upload" if you want to upload your own thumbnail. Click the "Browse" button to find a thumbnail on your computer and upload it. Enter the "Submit Code" and press "Submit Gallery".
Note: Uploaded thumbnails cannot be any larger than 88X88.
Let the script select an image from your gallery:
When this is selected the program will automatically select a picture from your gallery and use it for your thumbnail.
Select and crop an image from your gallery:
When this is selected you will be allowed to select any picture from your gallery and then crop it manually. Best way!