In my case, I select (open) the desired method to edit, and close the form with ESC, not with CTRL+W.
If needed, before ESC I press CTRL+S to save the changes.
There is a programmatic way, too. From the command prompt, type MODIFY FORM MyForm METHOD DesiredMethodName (check the help for MODIFY FORM)
Respectfully,
Vilhelm-Ion Praisach
Resita, Romania