how/where do you edit widget elements in dw cs4

I have included a photo gallery on my webpage.  when I tried to center it within the div the next/prev buttons ended up out of place.  Where/how do I move them to where I want them and how/where do I go to change the description text at the bottom of each of the clicked/large images.  The photo gallery/lightbox is from the Adobe Exchange below.  You can email me at donna.m@rogers.com.  Thanks for any help you can give.

http://www.adobe.com/cfusion/exchange/index.cfm?searchfield=lightbox&s earch_exchange=3&search_category=-1&search_license=&search_rating=&sea rch_platform=0&search_pubdate=&num=25&startnum=1&event=search&sticky=t rue&sort=0&rnav_dummy_tmpfield=&Submit=