In your members area, go to the "Advanced Features" page, then click on the "Misc" tab, then put the url for your webinar page in the "Redirect Page" field.
Put the full url, including http://.
Also, put ?user=~username~ at the end of the url so that it will go to the appropriate member's page.
Yes, it will suspend them. We caution to be careful if you have more than 1 tier, or an admin payment because the person gets logged out when only 1 of their possible many subscriptions is canceled.