Having that preparation phase is a good thing, I really like it, and I think most people do.
BUT, the button is done in a way that breaks the use flow. My suggestion to fix the issue with little work:
Put the button somewhere more central (nobody is ever looking at the corners), for example center top, or center below the player table. Also, giving it a more noticeable color helps, and maybe making it slightly bigger. Even the newest newbie will notice a central red button. But as it is now, nobody knows what's going on.
Putting the one thing that stands between you and the game far out into a corner is NOT a good idea.
Oh and in case you did it for consistency with the client: put it more central in the client too. Consistency is important. But constistently bad is not going to help
Allow us to play the game; don't hide the most important button in the corner.























