Inserting an event tracking in Axure for analytics

Hi there,

i’ve added the Google Analytics plugin to my prototype so that i can track traffic. It worked so far but i would like to add a tracking that would allow me to better segment the people who tested the interface. To do so i would like to send an event that would be triggered by selecting the segment in a dropdown. I’ve been wondering how to set this ?
Has anyone ever done that ?
thanks ^^