Why do you not want to answer this thread?(Your answer will be sent to Jeanette and Aytekin)
Cant save changes in designer mode. Try'ed catching form and browser it didn't helped.
I have just made the clone of your Form. And I am able to save the changes.
Probably it should be the issue of Browser Cache. I would suggest you to clear browser cache again, or try to check it in another Browser. Thanks.