Thanks for the feed back! The game has been updated and the mouse is now locked during gameplay. Esc or P will bring up the pause menu now. You'll need to press P or the continue button to un-pause, Esc will not work for this.
As for the graphics not fitting correctly I think it may be the pause menu/ pause button that you see at the bottom of the screen, if not let me know. Thanks again for the feedback!
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