The activity window may be showing the images in the gallery that are being preloaded by the browser. By default, SimpleViewer will preload the current page of thumbnails to allow quicker transactions between images (rather than loading each image only when it is selected which could result in a slight delay as the browser loads it). The images which are preloaded is controlled by the imagePreloading configuration option.
The download window shows only "Save as type: All files (*.*)" to save the images in the gallery exactly as they are (whether they are .jpg, .gif or .png files). (There is no option, for example, to save a .jpg file in the gallery as a .png file.)
However, having investigated further, there is a bug which prevents the Download Button for functioning when a baseURL is used which starts with a leading slash to denote the root directory (as used in Showkase).
I have logged a bug report with the developers and hopefully it should be fixed in the next version.
In the meantime, perhaps the easiest fix would be to open the generated gallery page (http://joehendricks.com/sv2/nicholasmeredith/index.html) in a plain text editor and change the baseURL in the gallery's embedding code from:
baseURL : '/sv2/nicholasmeredith/'
baseURL : 'http://joehendricks.com/sv2/nicholasmeredith/'
SimpleViewer Support Team.