Just gave this a quick go before I have to shoot out for dinner - but Jesus, that first level is tough and I've only just started it xD
So either I'm being a dumbass or something went wrong. I went into the theatre and the power went out. I went back out and turned the power back on, went back into the theatre and the power went out again and I can't see to reactivate it.
Nevermind. Found it. It was me being a dumbass. The map certainly feels larger than Basement which was nice. I did far more exploring.