Currently the behavior is to only update the icon if the Info Item is using the default icon for the original template. Since the Outlook message icon has already been assigned, the new template's icon won't replace it. Currently there isn't a way to achieve what you are requesting (other than manually assigning a different icon -- you could create an Advanced search to find all items where the Icon equals <Outlook icon>, then select all of the search results and change to the desired icon).
The difficulty is in normally executing the default behavior, yet providing an intuitive way for the behavior to be over-ridden. If you have any suggestions on how you would like this feature to be implemented, please post them to the appropriate forum or email them to
support@kinook.com.