So this is my logbook. yes i know i am late, but i've never heard anyone discuss this 'Laboratory' room. If you take the cursecone and put it beside the tunnel entrance to the dark room, a giant portal opens. What the ♥♥♥♥ is this?

I enter it and find props spawn. The prop limit has increased. However theres not much, only some interactive junk which leads you to videos on YouTube.

Then me and my friend solved the 'baby puzzle' with the doll, skull and 4 babies. A black-figure spawned, and after killing it a citizen food packet from HL2 spawns in. No idea what this does yet, i'll keep you updated.