Hi mark12341234. I'm sorry to hear you're having trouble with your CTC 101 registration. Would you mind providing some details about exactly what the problem is you have when you are trying to register the code? Like spycatcher2k, when I load that URL in my browser, I am presented with an input field for the registration code and a "Next" button. Do you see that also? I don't have a code so I can't proceed to check beyond that page.
Also I have emailed ctc.101@arduino.cc and have gotten no replies.
It's quite likely that the people who monitor that email don't work on the weekends, so that might explain the lack of a reply so far. Hopefully they will get in for work soon and reply soon after.