I got the "addresses don't match" message as well. Just a big FYI: the algo is pretty lame. I determined that my address said "XXX Road" whereas my teenage son's address was "XXX Rd." But the algo still said no dice. Turns out I had Zip+4 and my son's address only had a 5-digit zipcode. Once I fixed that, it worked.
As a former software engineer, I have to say, this is some amateur-hour programming.