Brilliant plugin, but I was finding it impossible to eliminate scrollbars in one of my sites using all combinations of maximum width, height, resize etc. It worked in some browsers but not others.
Then I noticed there is a new setting in colorbox 1.3.0 to turn off scrollbars altogether. This isn't yet carried through as an option in lightbox plus (1.6.3), so I've come up with a quick hack.
Add a new line 165 in lightbox.php as follows
Hey presto - scrollbars gone in all browsers and a lovely clean popup.
If that could now be a configurable option in lightbox plus it would make a great plugin even greater!