After some research it seems the problem is more complex.
After I've completed my form and than choose to edit I first get an error the only choice being to click OK. The edit form interface loads and the form is displayed correctly to the right but all the fields on the left where you would choose your basic building blocks are blank.
If I choose cancel - nothing changes and the form continues to work as before.
If I choose finish - the form is still intact but all data re: email setting etc. are gone.
After having chosen finish I can now choose edit and the form editor loads without any errors and without any email settings in place.
So every time I edit I need to do it twice and I need to re-enter all email data every time I edit.
I should also mention that when I choose finish Universal email server behavior no longer exists in the Server Behaviors panel.
I've attached 2 screen shots to illustrate.