Under the - EFFECTS tab it says//
"Here you can select the thumbnail effect, NextGEN Gallery will integrate the required HTML code in the images. Please note that only the Shutter and Thickbox effect will automatic added to your theme. With the placeholder %GALLERY_NAME% you can activate a navigation through the images (depend on the effect). Change the code line only , when you use a different thumbnail effect or you know what you do.
I selected "lightbox"
and this piece of code popped up
but what exactly am I suppose to do with this code?!!!
The default is so ugly!