It looks like you are loading in an external .swf for the
thumbnails and the larger images for each section. If you want to
update a particular section's photos, then you can just replace the
old .swf with a new one with the same name. Your movie will then
use the new .swf when it is called to be loaded.
You should not use getURL() for any of this. GetURL() is used
to load a new .html document into a browser.