Unable to complete Connect IQ SDK Manager account creation / login

As indicated in the title.

I downloaded the SDK and started the SDK Manager.  The first window popped up indicating a need to login to my developer account.  Pressed "Login", second window popped up a "Sign In" window with a "Create One" link.  Selected Create One, entered the info and selected Create Account.  Window goes to a single spinning gear...forever.  Start over, says account exists.  Try to login, now back to spinning gear.  Login never completes.

Any help?

Note this is on Windows 10.

Another note - retrying login with a bad password brings up an error box.  But login with correct info still doesn't complete.