membership subscription button problems

We are trying to go live with this site with the Membership plugin but are having lots of problems. Things just simply do not operate anything like we expected.

We are allowing people to register which puts them onto a subscription and level called "new-member".

We want the "new-member" people ONLY to have access to a button which allows them to move to a different subscription/level called "free-trial".

We have used the shortcode [level-new-member] to restrict access to a button displayed with the shortcode [subscriptionbutton subscription="2" buttontext="Activate Free Trial"]

MAIN PROBLEM: When a "new-member" clicks on this button, all it does is takes them to the account details page and doesn't change their subscription or level.

Once this is sorted it may answer some of our other questions related to display and operation of our paid subscription levels, but we'll see.

Please respond as soon as possible as we normally have about 1,000 site visitors every day and every hour this isn't working is money we are losing.

Thanks very much.