I came across this
http://www.oregonfirst.org/wp/wp-upl...onics_2009.pdf. On page 21 there is a great picture showing how to "work the wago". Important not to pry (which can result in flying screwdrivers!) but to slide the tip of the screwdriver along the back and down until it holds the wago slot open. Remove screwdriver once the wire is in place, test pull wire to make sure it is locked securely.