One more time for the hard of reading: it wasn't filmed at the Menier, it was filmed at the end of the subsequent tour in a venue ten times the size (the Palace in Manchester). Yes, it looks cheap in the film. That's what happens when you take something designed for a 180-seat theatre and shove it into a 2000-seat barn without rethinking it. It didn't look cheap in the venue it was designed for, and was actually slightly more elaborate in the Menier than it was on tour (in the Menier there were conveyor belts to bring set pieces and furniture on and off stage).
And yes, sure, it didn't help that Smith's performance deteriorated after the run at the Menier.