Using the condition IS EMPTY with the UPDATE / CALCULATE field is not working correctly

I have several condition statements that insert an email address into a field based on the value of another field.

When a value is selected, the operation works fine.

But if no selection is chosen (hence the field is empty), the condition doesnt work.

There are basically three scenarios.

1) select radio button gmail

2) select radio button fmrealty

3) dont select either

The first two send the email correctly, but the last one doesnt.  Is this a bug or do I need to use some other logic?

Thanks for your help. 

The condition seems to be working on your form at the moment.

If I am missing something, please let me know.