I haven't visited this site for a long time, but I tried it again today and it requires you to sign up, which I believe means you must have a Korean SS number. Almost everything Korean requires one. Without it you can't get past the signup prompt.
It would seem a natural feature to Koreanclass101 to have their own typing program. I think it would be very helpful, especially to their customers like me that don't live in Korea right now and have no SS number. Once the typing engine is made, it could be included in the lessons themselves.