Indeed it's terribly explained... I already got the compressor, placed it, got told to "power it" Edit^1*, and checked the entryway to core section, where I got told to find the maintenance tunnel on warehouse 2F.
---Looked around some more, and found an emergency power console in the Life Support section. At least now the actual problem at hand is solved, I guess.
1: So, retracing an older save, I did notice now you WOULD have seen the power console if the stand up image hadn't brilliantly covered it when you pass by. Not everyone happens to actually enter the room it's in, and I did actually happen to find repair point first and never encounter said console my first pass through. Issue two with this being most people would likely have tried to enter core engine at this point, and expect power to be in such a place, since that's how it is on your own ship.
A solution for this would honestly be not allowing the next quest to start until the air compressor has actually been powered... and tell the player to do that, if they try entering the core engine... allowing both quests to happen is likely the main source of all the confusion.
(sorry for the mess in this post if it's confusing in itself, a lot of edits have happened actually)
