Just purchased the pro plugin. The Add New Form page is blank in the “Form Editor” section (where it says “Click on a form element to add to the editor” in your demo version). When I click a form element, nothing appears to happen, but when I try to click the same one twice, I see “You already have this field in the form” in a dialog box message.
When I initially load the page, I sometimes briefly see the page contents load, then disappear.
I already tried deactivating all plugins to see if there were conflicts. This didn't work.