Not an error with this plugin, but people may experience a problem.
I found that the jquery.colorbox.1.3.32.js file wasn't being loaded when I switched on the WP HTTP Compression plugin.
As a result, the lightbox just wasn't working - clicking on an image took me to a page with that image.
This isn't just an issue with LB+CB - other lightbox scripts were misbehaving in the same way.
As a workaround, I switched the "Load in Header/Footer" option to "Header" (this is in Base Settings -> Advanced).
The script now seems to load OK.