Your page is in violation of Dynamic Drive's usage terms
, which, among other things, state that the script credit must appear in the source code of the page
(s) using the script. Please reinstate the notice first.
That said, the widget probably cannot initialize properly when it's display none, which is what the unseen tabs are in this script. When I have more time I will see if I can modify the script to use a combination of absolute positioning and visibility to hide the unseen tabs instead of the display property. That's usually what must be done to fix this sort of thing.
Edit: I Got the time:
First backup the .js and .css files you're using now, just in case. Use the updated .js and .css files in the attached archive (right click and 'Save As'):