Could be a combination of all of it, actually. I can think of a number of ways to make it work.
So one thing I’m noticing while trying to fit this map together is that the map layout overlaps, which is a bit of a problem. I’ll get back in a few, but it seems like some more rearranging and/or hallway extensions may be required.
I have a suggestion.
Can you add a change of lighting when the HEV Suit is acquired? like a change of color of lights or darken or something like that and when the door opens it’ll go back to normal?
EDIT: BTW, love that red light!
EDIT 2 : If the Hazard Course is still in the chapter list, can you make a chapter background for it?
Could be done, maybe… We’ll have to experiment a bit first to get a feel of what looks nice.
Just Dropbox’d a merged map. Ends in 05a, both in maps and mapsrc.
Currently the silo has a trigger that turns lights on and off.
Unfortunatly the lighting is not fitting with the silo its theme, so I’m not sure what it would feel like when adding a HEV light.
I’m planning to make a chapter background once the tram map is fixed.
@Dky I’ll get to it later today.
@Crypt The map compiled perfectly when it got orange mapped, and with basic lighting.
All the details were on its place, and all the brushes were fine.
I only added light entities, and suddenly BSP was complaining about leaks.
But all of those entities were inside.VVIS takes less then 0 seconds though lol.
Speaking of the silo, I redid it. You can go detail it if you want, just try not to mess with anything there, or move any brushes, 
I looked at your map and it had gaping holes in the walls. I don’t know what you did, but you obviously did not do it right, and adding light entities was not the cause of the problem.
VVIS takes 0 seconds because VBSP generated 0 visleaves, and therefore it becomes impossible to build any sort of visibility matrix and so VVIS just flat out refuses to run at all. Also because there is no visibility matrix, VRAD will refuse to calculate ambient light bounces which means it will have a shorter compile time as well… but generate unrealistic and crappy lighting in the process.
So then when you get dropped into the game, the engine will just render the entire map at once because it has no idea what is supposed to be visible and what is not, which drops framerate and destroys playability on lower-end machines… and on larger maps that have more polys, it just flat out makes the map unplayable on any computer due to video lag.
It’s NOT a good thing. You CANNOT have leaks. Period.
EDIT: Read up.
I’m gonna give the detailing a shot.
Are you done with the redone of the 1st room though?
@Dky Alright, that means I’ll have to pay more attention when mapping lol.
Yeah, it and the silo were redone, thy just need some more details. Look at t0a0_05a in my folder and use that.
BUT I’d recommend reading that leank (I know, shut up) Dky just posted, as well as on properly using func_details, and staying on the damned grid. Seriously, and if it just refuses to snap to the grid, try pushing Shift+W to make sure snapping is enabled. It’s a huge problem.
Mind if add the elevator, to enter the first room?
EDIT:Nevermind, props are sticking out ;p
EDIT 2:Why is the silo blocky?
EDIT 3: Does the silo still need a trigger_hurt or water and a trigger_hurt?
Eitherway gonna draw some concept art for the physics room and see what I can do.
If I download the version you have with whatever changes you’ve made (if any) then I can add it in.
I litterally have no idea what I can do with the physics room lol.
Whats with the catwalks though?
Eitherway, I like the idea of the box system but it does not really make sense to me that a system like that can already be in it.Unless the conveyor belt leads to the warehouse full of ammo.
I added (and changed) some props in Crypt’s map, mine is named ‘hc_t0a0_05a_130104.vmf’. Have a look if you like.
Vmf updated with a placeholder elevator shaft and Lars’ changes. Renamed to “06a.”
Box, why do you keep putting all the doors upside down?
I’m actually not a huge fan of the water in the Silo. It prevents player death, and if you put a trigger_hurt in it, that destroys the player’s sense that water is supposed to negate all fall damage.
I say put a grate over the water. That way you still get water, but the player still dies. And we may as well make the pit deeper, anyhow. I like vertical space, in case nobody’s noticed at this point. 
EDIT: Crypt, hc_20a0_06a.vmf has leaks. Those elevator trusses are located in the void… Might be worth fixing.
EDIT2: It’s an easy fix. Just expand the wall brushes to 32 units wide to cover the truss origins and VBSP will stop complaining.
Really? Looking at everything I would have never guessed!
Oh, I though I’d already done that. Guess I forgot. I’ll get it, now, then.
Is it not better to make a bottemless silo of it?
Or just let it fade somewhere before the player dies.
Eitherway, as for Dky’s [redacted ] extra in the physics room, shouldnt it have a button?
Or else we need to put a laser though.
Um… What?
Edit: Dropbox’d the silo. Remember that the merged maps are more of a layout reference than a file you should actually be using. All of them still need to undergo lots of changes before they’re ready for a final merging.
You need to see the extra Dky put in the physics room