Thank you for your reply.
I see the steps for adding Exchange properties in the View menu in the tutorial you listed, but I'm trying to allow the user to modify them via a 'modify' action on the homepage.
From the user perspective, the workflow should be - Sign in to the Adaxes front-end, select Modify Contact (which already has my customized form), select the contact to modify, input the properties, and save.
My custom form already displays all the AD fields the user cares about - name, address, email address, etc., but when a change is made to the Email address in particular, it will only change that field in AD not in Exchange. For creation, I have a business rule that adds the email address to Exchange when a contact is created, and I want to do something similar for modification.
Please let me know if that's unclear at all, as I know the terminology involved here is all very general. Thank you for the guidance.