Hearth is such a cool concept for a map, but the 3d skyboxes need some more work in its art passes:

• The planks of the train tracks for certain warp locations are blatantly textureless on the front and back but not the top and sides.
  
  
• The environments themselves sort of feel out of place when looked at by a player due to their lighting. You'd think with the train's singular front beam on full-blast, it would illuminate the tracks at least a bit, but because of how the 3d skyboxes were done, that's a no-go. Especially in the hell location, everything is so incredibly dark. I'm hoping this isn't a limitation of the source engine because the skyboxes are just one big model told to move slowly across a straight line.
  It looks great on its own but when you compare it to how bright the player's weapon is or how lit up their playable space surroundings are, it's rather off-putting.
  
  
• The wooden bridge between the floating town islands in the purple void location looks nonsensical, the wooden planks are so massive and far apart that anyone living in those houses would need to launch themselves from piece to piece. I get that it's meant to be like a dimension of madness or whatever, evidenced by the train tracks going into a ridiculous swirl before reaching the castle, but the town houses themselves look deliberately proportioned to their little roads, not randomly sized and bulbously shaped or anything. I dunno, feels like an inconsistency in the art direction for that environment.
  
  
• The displacements that were likely turned into models via propper didn't use any alpha transitions for the textures, so you just get a hard transition from grass immediately to rock on a solid line that separates the two. Dunno if this is because propper just ignores alpha transitions on displacement by default, or because it just wasn't something you bothered with when making the 3d skybox locations, but either way it's a bit of an eyesore to see hard texture transitions that are so wildly different in color from each other, not to mention how some of the textures feel a bit too up-scaled and thus ultra-low res to look at. But I understand that that's more just a limitation of the textures you had available that would be blown up by the sky_camera than anything else. Still though, some custom HD textures designed to be plastered over a (visually) huge space would be a massive benefit for a few areas, especially the circus canyon.

I really really want this to be added for a scream fortress update but it isn't really ready yet. I may be biased though, because ctf is my favorite gamemode (even with its tendency to become a dragged-out endless deathmatch). The concept itself though is very wild, and is exactly the kind of crazy s**t scream fortress needs. The layout is diverse enough that it's easier to escape with the intel than to defend it, better ensuring rounds that don't become a nightmare-ish stalemate, though I do rather find myself disappointed that there's no scream fortress mechanics of any kind to be found. No spell books, no bosses, no wheel events (even though they're usually just annoying and yes I'm aware the original had it tied to the actual train warp as I recall) not even pumpkin bombs. Nadda.

Please keep working on this map. It has so much potential to be a crazy scream fortress map, but the main visual gimmick of changing 3d skyboxes seems underdone at the moment, like it's only a rough draft. I recommend thinking carefully on what scream fortress mechanics would benefit ctf, and then implement them. Though, to be honest, considering how cool and unique the changing 3d skybox mechanic is, I would press you to get some additional help on the project and make that skybox changing mechanic not only much more visually impressive, but also impact gameplay somehow.

Here's a few wild ideas off the top of my head:

• Have the train go down a steep incline and pick up speed significantly which pushes everybody backwards somewhat (if you were outside), and if you don't have something to stop you or if you aren't a scout, you'd soon go falling off the edge. As the train gets to the bottom and back on flat ground, the change in direction at high speeds temporarily raises gravity to make jumping more difficult (except for jump pads in the map, of course).
  
• Have the train go through a location that has a magical green meteor shower that plops down halloween explosives (similar to the pumpkin spell bomb) all across any exposed areas of the map layout, slowing travel outside of your train until you've destroyed the ones in your way or risk it and move through anyway.
  
• Have a location be a big hilarious swarm of eyeballs in a thunderstorm, and it spawns in the monoculous for the duration of the train being present in that location.
  
• Make a new location that's a toy train in Merasmus' apartment, and he shrinks down to your size and fights you until you warp elsewhere.

Seriously though.... huuuuuuuuuge missed opportunity in the underwater location to have the silhouette of some massive creepy oceanic beast lurking in the distance or directly above.

Overall, it's pretty good, but it's far too close to being great for me to say it's ready as is for Scream Fortress. Make the skybox locations the train visits be more dynamic. Visible lightning where you hear it at places like circus canyon or the big river. The volcano should be spewing lava/fire particles in the hell location, etc etc. Also try to make each location impact gameplay somehow to add to the chaos that is always a Scream Fortress map. The more creative you get, the more fun contracts can be. Imagine everyone scrambling to change what they are doing once the train visits a particular location because their contract has a requirement only that location will temporarily allow. It could be bananas if you went all out on it. Certainly the greatest possible first impression an officially adopted CTF Scream Fortress map could have.