XML Photo Gallery

I’m trying out the XML Photo Gallery code and have a few questions.

How would I (from a button) dive into a specific node within the slide show? Say I have 10 images in my xml file and I want to take the visitor to photo 3 in the side show and then advance them from there.

Also, how would I disable the next button when the end of the set has been reached? And also disable the previous button when starting out from the first photo?

Lastly, how would I position my photos within the empty MC? Do all the images in the XML file have to be positioned the same?

Thanks!
Angie