I guess from your emails you mean going into editing mode?
Apus goes into editing mode whenever you are editing text, so if for example you add an S to an existing word it doesn't try to complete it to a word starting with S.
It goes into editing mode if you move the cursor with the arrow keys or the mouse, or you click in a new window. This is unavoidable - because of the low level Apus works it does not 'know' what is behind the cursor when you move it, it only knows what you have typed.
Tom