Amnesia: The Great Work - FULL RELEASE

[Tetrafish]

Okay, I've made into the Cabal, and got to a room...

Spoiler below!

In the room above I turned a valve after moving a torch underneath a tank. The green liquid dissolved a gate and I used a ladder to get down into where I'm now stuck. I did get a Cabal gate key... But there are 2 locked doors and I don't have any other keys to open either of those 2. I can stack boxes on top of the acid(?) and jump up to the ladder, but there doesn't seem to be any way to get off the ladder into the room above. If I try to jump out/off I just fall back down.

EDIT: Alrighty, I seen the puzzles video, makes sense now.

If there's still a way to get out then let me know (not necessarily how to get out (or maybe I missed something like a key..?), unless it's just stacking all the boxes, because I'm trying that but not able to get them high enough, if that's the solution then I'll just skip this whole area). Or if I'm stuck then let me know that too. Thanks in advance.

..Can't get the Brute to appear, looks like it may be too late at this point. I do have/did have

Spoiler below!

the dagger and stabbed the heart instead of picking it up.

Edit2: I started over, did it a bit different this time. I followed the monster into the Cabal. After I came back I ran around the Sanctuary... I got killed by a cultist (I could never get the 2nd dude to come out). When I respawned I went back to the elevator. I was able to get on and into the next area and thus Exit.... BUT! I never went through the other gate to get (what I guess would be) the blue piece of the shard....?

I hope I won't need it, or that I'll be able to return to that area. I'll play it through to see if I get any game breaking dead-ends.

Edit3: I guess I had all the shards I needed. I'm not sure where I picked up the one I needed since I skipped that one whole area.