Played it today. Didn't finish the first map because of the damn random Facehuggers. Finished the second one without completing a single objective. I didn't finish the third because of the androids constantly swarming me. It's just too damn hard. No checkpoints, no nothing. It sucks all the fun out of it.
They should have just done a decent story campaign set before the events of the Torrens arriving with a proper narrative.
I agree with the lack of checkpoints.
I honestly thought the developers would have tried harder to make the whole DLC story get together but there are no cut scenes or any dialogue to progress the story at all; the only thing you get is a computer terminal with one message.
Btw, I figured out how to read it without getting killed, it seems the Alien is programmed to come into that room whenever you interact with that computer whether it's to hack it or read it so be sure to hide in the nearby cabinet when you're done using it; non-scripted Alien encounters, my ass.