I had issues registering as well. I finally figured out that the name must be exactly as on the e-mailed receipt they sent you and your password MUST include upper case AND lower case letters AND a special character (I used a "#").
Also, I copied and pasted my member number from the e-mailed receipt but it must have been putting in a space at the end of it when I pasted it onto the registration form. I pasted it somewhere else, removed the space, then copied and pasted again.
After all that it finally worked.