After download, cannot find dashboard to login & setup Pro version

I added your WP Smush free plugin today, then agreed to the 14-day free trial. It has not upgraded automatically, and I can find no way to complete the WPMU Dev Dashboard install instructions. I've downloaded it, but there is no place for me to "login to complete the install." We're Native creatives on a reservation with bad connectivity, & I'm at my wits' end dealing with urgent image compression needs that are crucial to our livelihood.