The slideshow is great - very useful & relatively dynamic. The UI is easy & useful - I enjoy not having to open & select each image individually. Perhaps up/down buttons for switching image order? It can be difficult to drag something to another space that's far away. I'd like to see some improvement on the fade transition -- fading between images instead of null space.
What I'd really love to have is more options for customization of content. I am duplicating another site in which you can click on an image in a slideshow and it opens up in a lightbox gallery. I have a favorite that I am using for galleries - prettyPhoto - but it requires (rather simple) markup using the REL attribute. You also have the option of specifying a caption with TITLE. I tried editing the code to make these available and got the UI to include them and the display to (potentially) include them, but I could not work around the parsing. I could not even include it by cheating with the URL box - my extra info kept getting thrown out, and I couldn't figure out what to edit next to keep it from doing so. I ended up having to write the REL attribute directly into the display code (only in one place - otherwise each linked image is included multiple times). Anyway, extra attributes for the A and IMG tags would be much appreciated!