Same problem for me.
Using a Roku stick.
The app never starts. When you click ithe rtveplus channel, it shows a wheel and it says "cargando" (loading) only for a second, and then it disappears an the tv is all black.
Sent email to RTVE and they said it is not their app problem, it is a Roku problem. Frustrating.
The app works fine in Android tv.
@LaRoja, RTVE is blowing you off. Roku isn't going to try to figure out why a channel/app they didn't create doesn't work. The Android app has nothing to do with the Roku channel/app. They couldn't be more different.
I know.
All I'm saying is if you want to use the rtve app, use the apple tv.
Roku doesn't care.