If you open two or more files, then modify or delete all of them from outside CB, the "File changed" dialog pops up. If you click yes (keep it open), then you get a dialog for each file. But if you click no to the first dialog, the dialog is shown for all files but not for the last one.
Now open three or more files, delete them from outside CB. Restore CB, click "yes" on the first "File changed" dialog then "no" on the next dialog. Something strange happens, the cb editor is divided in two or more editors, and if another dialog appears and you click "no", CB stops responding and crash after a while.
EDIT: wait, i can't reproduce again this bug..
I'm using the last nightly build (1853).