Membership 2 Plug-in (4.x) activates but brings site down

I am trying to use the Membership 2 plug-in - and I have disabled EVERY OTHER plug-in. As soon as I re-install / activate the Membership 2 plugin - my site freezes until I delete the Membership plugin folder from wordpress.

I don't know how to get past it - I am getting frustrated as this is a vital part of a revenue generating website. I need "live" assistance. Can you provide that?