When creating the Colony 19 (sci-fi/near-future) floor tiles, they were designed so that when you create an encounter map with the tiles, you then have to place a fold-up door assembly in the gaps between any of the rooms/passage that you want to connect together.
For example, if you set up a couple of the tiles to look something like this:
This has the benefit of having the doors being placed in an area that does not interfere with the placement of miniatures, while also allowing you to only place doorways in the specific areas that you require them (though you do have to ignore this imaginary gap between rooms/passages when determining movement and range - as the tiles are a little abstract in this way).
However, since the tiles were released, I've had a couple of comments/requests with regard to making open versions of the doors, or perhaps separate (2D) doorway tiles, etc.
So what I have come up with is a set of (2D) overlay tiles that can be used to depict closed doors, open doors*, and also glass panes, that look something like this:
All of these work in exactly the same fashion as the existing (3D) door assemblies (i.e. just place them in the gap between rooms/passages to make doorways into those rooms/passages that require them), and should be available as a free download as soon as I manage to put the pdf together.
So if we take the same example layout from above, and add a few of these overlays, it should look something like this:
Hopefully this makes all of the tile-sets a little more user friendly, and also offers an alternate way of connecting the tiles together.
(* Note that these can also be used in conjunction with the 3D doorways if you wish ...simply use one of these when the door is open, and place a 3D door assembly on top of it when it is closed.)