Hmmm at a glance everything checks out OK as far as your installation of the script. I see the problem you're describing. There are a few JavaScript errors thrown from some of the other scripts on your page not related to Tab Content script, such as:
Code:
Error: this.$events[type].keys has no properties
Source File: http://www.quarterlives.com/wp-content/plugins/content-gallery/scripts/mootools.v1.11.js
Line: 3
My guess is when the browser encountered those errors, it halts/ disrupts the execution of Tab Content script as well. To confirm this, create a page stripped of all other scripts except Tab Content script, and see if that fixes the problem. Then slowly add back the other scripts to see which one is at fault.
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