Using Easygallery in one of my websites

Hello,

I downloaded the easygallery script and integrated this in one of my websites (which is not yet online).
I am receiving an error message at the bottom of my screen as soon as I move my cursor over one of the pictures. The errormessage I receive is the following : "invalid argument" and this for every foto ?

Does anybody of you experimented the same type of problem with this script ?

thanks in advance

Wim