Hi... I was reviewing this and thought I would post a few comments.
I know that the from email address can be defaulted to "Blank" and it will default to the portal admin from address. This is not the case for the "to" address.
I would recommend doing the following:
1. Create a hidden field called "AdminTo" and use the feature "SQLDefault"
2. Set the SQL Default value to be a query that references the portal administrators email address. This would likely be pulling from the portalsettings table against an inner join with the users table and possibly even the userroles table. This way, you would be able to utilize the IPORTABLE feature by referencing the short field name within the email completion event. So instead of sending to the address@domain.com you could send to $(AdminTo) and it would always end up sending to the admin. Your query for SQL Default could reference $(PortalID) which would allow you to specifically get the portal admins email for that portal.
Hope this helps! If you need us to be more directly involved (such as writing out the SQL queries and so forth) we can do this via our Premium Services. To get started or pick up development time you can navigate to
http://www.datasprings.com/hours. Thanks,
Chad