If you havent already, then for full access to courses you'll need to take a few seconds to create a new account for yourself on this web site.
Here are the steps:

1. Fill out the New Account form with your details.
2. An email will be immediately sent to your email address.
3. Read your email, and click on the web link it contains.
4. Your account will be confirmed and you will be logged in.
5. Now, select the course you want to participate in.
6. You can now access the full course. From now on you will only need to enter your personal username and password in this form (or the form on front page) to log in and access any course you have enrolled in.