I can type into the beginning of a file, but I can't backspace or move the cursor position at all. Ctrl-Z does not undo. This happens if I edit the file from the context menu, and when I open it directly from within the editor. Also occurs when creating a new file: I can type all day long but I can't backspace or move cursor position. :-/

This is happening to me as well. Uninstalled and reinstalled and it still occurs.