Modify "Registering for this site is easy" with Membership plugin

Hello,

I am trying to modify the text on the Registration page that says, "Registering for this site is easy, just fill in the fields below and we’ll get a new account set up for you in no time."

I was following these instructions from BuddyPress:
http://codex.buddypress.org/getting-started/customizing/customizing-labels-messages-and-urls/#poedit

But it's not working. Is the Membership plugin making this not work?

~eric