That reply from Paramount was completely unacceptable. Even though it is clearly a CBS Interactive issue, and not Roku, we've had to leave the platform entirely and go to Fire Stick (where it appears to work) as it's that big an issue in this house. But MANY thanks to everyone here for the suggestions.
Create a new profile and enjoy.
You are a life saver. This is all that worked for me.
Easy fix! Just click on "watch credits" and you can now rewind to the beginning of the episode you want to rewatch.
It would be nice if there was a rewatch option, but this will work for now.
Select to "Watch credits" and then mash the heck out of the replay button (button with the circular rewind icon on it). I press the button about 6-10 times very quickly and the video goes back to the beginning.
That only works if it's not the very first episode.
Doesn't work if there aren't really any credits. You don't have time to do anything. It's like the people who designed this have never streamed shows before.
Use a different profile