I encountered another issue w/ my mechanical switch and opened a ticket, waiting on resolution. The new longer button is not the same diameter as the original button, thus the copper contact ring does not sit snug on it. I set my Protege down, button up, and evidently the copper ring sat on the aluminum contacts as opposed to retracting with the button. I only noticed when I smelled my atomizer burning up (literally).
Back to the tact switch...........
I had this problem too. Mine will actually fall off the new long button.
I cut a really thin piece of gaffer's tape under it to help hold it in place.