I'm just hooking the unit up to the tv and was wondering if I can leave the lid down overnight? I do see that there won't be very much circulation when it is down

No. The owners manual states you can leave the fridge on while traveling down the road but once you stop, you should lift the top within an hour. An hour is all they recommend leaving the top down for while the fridge is on.

I am leaving it plugged in overnight, I did raise it so there will be some circulation

I wouldn't lower the top with the fridge running. You run the chance of the fridge overheating and no place for the fan to exhaust the heat. I think you are asking for trouble if you do. Leave the top up, better safe than sorry.
That is my opinion.

Bob

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2014 FR Heritage Glen 282RK
2013 F250 HD 6.7L Diesel
Formerly Owned: 1995 22D Fun Chaser & 2901L Classic

Have your ref. as level as possible when you packing for a trip. I agree that the ref.needs full air circulation and the trailer needs to be kept in the up position. Pre chill and freeze items. Have a funtime on your campout.