See below the feature comparison table for the SuperSKa Picture Gallery:

Feature	Free Version	Version 2	Version 3	Version 4
Configure Thumbnail Position
Configure Thumbnail Position
Preview Counter
Configure Preview Size
Original Image Popup
Upload Single Images
Upload Zipfiles
Supported File Types	jpg, png, tiff, gif, bmp
Lossless Rotation
Respect Portal Space
Fully Localizable
Search Enabled
Add Description Per Picture
Configure Thumbnail Layout
Hide Preview Counter
Authorization For Original Image
Secure Storage Of Original Image
Works With Thousands Of Images
Function To Remove Orphans
Uses AJAX see the difference
Supports Import / Export
Import Files Already Uploaded
Automatic Sorting
Improved Performance (Caching)
Supported DotNetNuke Versions
3.00.12
3.00.13
3.01.00
3.02.02 / 4.00.02
3.03.03 / 4.03.03
3.03.07 / 4.03.07
4.04.00 - 4.07.00	Unsupported And Untested
4.05.00 - 4.07.00
4.08.00 - 4.08.03