It actually sounds as though you are using the Sling TV channel on your Roku, instead of the SlingPlayer channel on Roku. The SlingPlayer channel for Roku will not ask for an email address and password. The channel itself helps the SlingPlayer, on your phone, establish connection to the Roku. In the event you are using the correct player here is an article with some troubleshooting steps to try:
Hope this helps!!
I've downloaded sling to my roku. I have the latest version of the sling app on my phone. But I'm unable to make sling work on my roku. Two problems. First, I can't sign in, as required by the sling app on roku. It says I need to register at www.slingbox.com/roku. But there is nowhere to register for using sling on roku there. When I try to log in with my regular ling password and email, it says I'm using a wrong email or password.
The other problem is that when I look for the roku option on my sling app on the phone, it's not there.