Trying to switch from Interactive to Professional Course

Just signed up today.

Spent 30 minutes on Interactive courses before I realized that the Professional one is better suited to me. At least I think so, I cannot start it, since I cannot skip the lessons I have already done in the Interactive course (basis Home Row stuff) and I do not want to do this all again!

Just to be clear, it says I am lesson 4 of 29 but when I click the forward button to move to the next lesson nothing happens.

So how do I check out the Professional course without repeating already covered material?