I've been told it is not possible, but is there any way to change the thumbnails for about, sitemap and contents? I have turned thumbnails off in the web version. Thanks.
In general (not for most, if not all, bundled skins), depending on how the skin works, it is possible to change the icon, either in just the album or in the album and the explore view.
The skin must use the jAlbum default icons, not use their own icons or font based icons.
For the album only you just add a png image named the same as the default image, for template page like about, contact etc. you would add your own htt.png file to the project's 'res' folder. For both the explore view and the album you add the file to the skin's 'res' folder instead. Obviously the file would need saving somewhere else and adding back to the skin after any skin update.
This information is just so you know, should you want to use a non-bundled skin that uses the default icons (found within the applications own 'res' folder.