Upgraded and product pages are now blank

Upgraded the site yesterday to 1.5.1 and now my product pages are blank. Winmerge told me the files should be good. Can't figure out why those pages aren't showing up.

Even new products are blank once I create them.

Site is here

http://lehighequips.com/

and it's live.

Any one can help?

Winmerge told me the files should be good
With all of the changes in this version HOW did you determine with winmerge that they are "Good"

Try switching to the classic template and see if they display

If so, then this points to one of your overridden template files

Also, check with FTP and look in your /logs folder for any errors

About blank pages: http://www.zen-cart.com/content.php?124-blank-page

About upgrading: http://www.zen-cart.com/entry.php?3-How-do-I-rebuild-my-site-on-the-new-version-instead-of-upgrading

I went through them all on winmerge and the only thing that seemed like it needed to be carried over was the language files, which I did and they're showing up fine.

Category pages are showing fine, it's only the individual product pages.

I did switch to the other template and the pages are showing...and this is the only error I'm showing inside my error log files.

PHP Fatal error: Call to undefined function zen_lightbox() in /home/lehigheq/public_html/includes/templates/lehigh/templates/tpl_modules_main_product_image.php on line 24

Forgive me, I'm not an expert at this. I followed the migration and upgrade steps one at a time and did it. It was working fine in the temp folder before I moved it all over live...now I'm not sure which files I've missed.

Call to undefined function zen_lightbox
Did you miss installing/copying the ZenLightBox addon??