The NWC Upgrade FAQ indicates that List forms cannot be upgraded.  I have almost 300 SharePoint O365 List forms that I would like to recreate in NWC.  I thought about leaving them in SharePoint and starting the NWC workflow on a new or modify event.  However, I will lose the "My Nintex" functionality of "Submit a form", "Form submissions", "Favorite forms" and "Draft forms".

 I have tried to "Export" the form from SharePoint and Import the form into NWC, but I get the error message: "This form is incompatible with this version." 

The forms are quite complex with many rules, so it will take a life-time to recreate them.  Is there anyway to copy a SharePoint list form over to NWC without creating it from scratch?