K2SmartForm looses its K2 Mappings (sort of)

I have a K2SmartForm.
The form is a PlanPage and is mapped to a K2 Project action.
When I try to run the project to preview the page, I get the error as in the attached image.
To solve the error I have to go to the K2 mappings and change the mapping of the action to another action and then reset to the original action.
Then when I run the VS project, it works fine... for a while until I'm forced to repeat the process.

Anybody ever seen this?

Any ideas on a fix or workaround?

Thanks
C