Re: Forced perspective, painted backdrops and the refit Enterprise
Wasn't the door supposed to be sealing off the Main Engine Room from the effects of decompression in the other chamber? I think it is mentioned in the novelisation, and everyone certainly leaps for their "respirators" once reminded.
Yes: "The breach in the hull sucked air from the engine room".
Unfortunately, with the "fresh air pouring into the depressurized area" they also had "poisonous coolant gas flooding the trainees' area" because of leakage.
"The first duty of every Starfleet officer is to the truth" Jean-Luc Picard
"We can't solve problems by using the same kind of thinking we used when we created them." Albert Einstein