I've created an OpenShift Application from Eclipse IDE providing it an Eclipse Project as input.
Then I tried to create a server adapter for this project. It didn't work initially because the project isn't a Faceted Web project. I had to quit the OpenShift wizard, make the project a faceted one and restart the wizard.
I would expect the wizard to create a server adapter to suggest and link to a way to make the project associated with the application a web project in Eclipse IDE so it's one less step to understand for users before it works.