Something I remembered and checked a moment ago is that it's possible to read from the maps in which sequence objects were added, which can be a fascinating door into speculation. From a glance it appears as if the toilet was the starting point for developing that part of the map, and this was estab...

An interesting question. So everything seems to indicate that this piece was part of the very end of Blood's development cycle. I can't find anything to support it being repurposed from earlier maps either - it bears no resemblance to Raw Sewage, for example. The passages themselves are fairly well ...

I don't immediately recognise the above. Sounds cool, though.
Some of the older custom single Blood maps had accompanying midi files, but I suspect most of those were "borrowed" from other games.

For flags, check out my third bulletpoint on page 8 of this thread.

BloodBath and team player spawn points use the same sprites. What you could attempt is to flag a series of eight of them for BloodBath and then flag another bunch for teams only. It's not something I've actually tried before, but it might do the trick. There is unfortunately no way in which to speci...

The "1 way wall" is done through pointing towards the wall you want to create this effect on in 3D mode and pressing "1". This will flag it as one-sided. You may want to change the elevation of your sectors to enable this, since depending on what you're doing, you do actually nee...

Oh, I see, so you want to literally copy Phantom Express' ending. Yes, music is dealt with at the .ini file level. The map itself has absolutely nothing to do with that. So what you're looking for with regards to the two switches is a combination switch of type 22. This is handled the exact same way...

With that question, it's time to introduce the concept of time-delayed triggers. There are a few ways in which to achieve this, but here's my go-to solution. An image will illustrate this nicely: . 19.PNG You would need something to this effect. Here's what's going on: This is a switch which receive...

Which part of E1M3's ending are you looking to reproduce?
Your assumption regarding the little opening vents is correct. It may take a little tweaking, but fundamentally it's a vent with a push trigger that activates a rotate marked sector.

Easy as pie. You will need to provide a TX from a sender of your choosing. You will then make a sprite or series of sprites in the appropriate locations of Type 18: Dude Spawn which receive that TX. The final step is to then add a Data1 value that matches with the monster type. For instance, Data Ty...

Excellent. Sounds like things are coming along nicely.

Glad to hear you solved the box conundrum. Your situation sounds a bit tricky in the way you're trying to structure it. The first step is to see if you can even command a door that requires a key to open using triggers. Again, this is pretty unorthodox and is something I've never tested that I can r...

Two more suggestions. Delete the boxes which aren't working correctly by mousing over them and hitting CTRL + DELETE to make them white and then "make them red" again. If after that they still aren't working correctly, assign the same lighting effect to the boxes themselves.

My suspicion remains that the walls of the crates have bottom-swap on. Go to the ceiling/sky and unparallax the offending boxes, bring their 'ceilings' down, then mouse-over the corresponding walls and press '2'. See then if the 'bottoms' of the crate walls, i.e. those in the room are behaving after...

Depending on the scale of things, you may need to have a second door which closes which is the one that requires the key. There is no way in which to switch a door from requiring a key to not requiring a key in Blood. It is slightly unorthodox for Blood, but it should be fine for you to proceed with...