[Plugin: Google Analytics for WordPress] Single Category custom variable BUG

Hello
On the settings, I enabled many custom variables :
Post type, Publication year, Single Category

The day i enabled it, when i check on my google analytics account, i had all of them working. But just a few days after, i went back and noticed that the pluggin stopped to track the Category variable.
Post Type and Publication Yaer are still tracked, but Category is not tracked anymore, it only lasted a few hours.

Any ideas why ?
Thanks a lot

http://wordpress.org/extend/plugins/google-analytics-for-wordpress/