UPDATE:

ZeeRock,
try installing fual_slimbox.v0.1.5 . Follow the instructions for Zen Lightbox 1.4 users . I have ZL 1.5 but it worked fine for me.

My jscript problem disappeared with the installation.

Note:
I had to remove the ZL css in order for the styling to look right in the new fual pop up windows.

Hope it works for you! I've been banging my head on this --what should have been a very simple --thing for days.