Hi Brian, when you've entered a number, nothing will happen immediately.

What should happen is if you move your mouse back to that line, you should get some new snapping points on it (like 1/5, 2/5, etc...) .

Do you possibly have "Object Snap" turned off? I mean is it not highlighted in orange on the bottom toolbar?

The div snap is a type of Object Snap, if you have object snaps disabled (the button not highlighted in orange) the div snaps will also be disabled, is that possibly what you are running into?

- Michael