I've gone through the process of beginning the $5 Email Client test that you offer. I received an invoice right away but the page is stuck on the LOADING screen without showing any screen captures.
I have used this feature before and never ran into this issue. It has been on the LOADING screen for close to 1 hr.
Are you still showing a stuck screen? Please contact support with your account details and we can take a look.
It looks like we helped you out via support with this. For everyone else, the test was complete it was just the browser having trouble loading it. Sometimes what helps in those case is to leave the test page and go back into it.