Authorize.net Trial Membership Limitations & Setup

Hello, I am trying to create a 15 day trial for $0.00 followed by a $6.99 monthly charge. Turns out that's not possible in Authorize.net and its not in Membership Docs. You can't have a Trial period (weeks) Different than the Recurring period (monthly ), which created odd dates in authorize.net. So I would add it to the manual, but please let me know if this is setup correctly...
http://screencast.com/t/iswFDOUM1hk9

IN Authorize.net it shows as a "PREAUTH" charge for $6.99, rather than a $0.00 charge , (meaning just looking to see if customer has funds, no money actually taken out) . Then a Recurring bill setup in 30 days. Are trials suppose to setup a PREAUTH? Sounds like a good plan, if correct.

Did I set it up correctly?
Thanks