Hi Cindy-
When you say "registration button," are you referring to the one at the top and/or botton of the event summary page or are you talking about a "widget" button that will link to your Cvent website?
If you are referring to an email, I use the datatags that allow you to link to specific pages. These do become available for testing when you are accessing a "test" link from your site. Steven is correct that the actual link that you find in the "weblinks" area will not be accessable until the website is "active".
Happy to help if you need anything further!
------------------------------
Lindsay Buchanan
Manager, Meetings, Association Management, and Groups
Travelink
------------------------------