I'm having the same issues. I have tried logging in with Facebook and it just doesn't allow it to go further and I tried resetting my password but it doesn't allow me to log in after resetting my password either.
I am unable to login at https://play.spotify.com/browse. I'm attempting to login with the Spotify login rather than the Facebook or Google+ login methods. I know my details are correct as I'm able to view my account.
I am having this problem also. App hangs on log in on Win 10 PC using Google Chrome. I see all kinds of work around suggestions posted throughout the forum, but is there an official Spotify approved/recomended fix ? If so appreciate if someone can point me to it. If not, Spotify folks, get on this fast... it's a fundamental issue !