A quick, crude guide to setting up your TF2V FastDL server.

Step 1: Converting your maps to .bz2
Converting your maps to .bz2 allows them to be downloaded much faster than in .bsp format in most cases.
A more detailed guide can be found in the TF2Vcaddy/site/tf2vintage/maps folder,
but the short version is to use 7-zip to convert a .bsp into .bz2 or your program of choice.

Step 2: Adding the maps
Once set up, you need to add the .bz2 maps to the proper file location, which for TF2V is TF2Vcaddy/site/tf2vintage/maps.
This means that the FTP server will check the tf2vintage folder, then the maps folder, then see if the map is in there.
If a map is not in there, it will download the map directly from the server.
You do not need to restart the server software (Caddy) to add new maps, 
but you will need to reboot your TF2V server (SRCDS) to add/remove maps from the maplist.

Step 3: Configure the server
Caddy is a simple webhosting platform that supports HTTPS, and can be configured to do a lot of different things.
By default, TF2V's Caddy is configured as an FTP server by default on port 1236. You can change the default port under Caddyfile as :Port in the file.
Once the port is set, simply run Caddy.exe and forget about it.

Step 4: Open your ports
Since this is an additional server, you'll need to open the port to allow people to download from it. 
By default it is 1236, but depends on if you set it to a different port in the previous section. 
You should be familiar with this section if you are already hosting a TF2V server.

Step 5: Set your maps in TF2V
A fairly obvious yet overlooked step. Remember to add the map to the server by adding it to the active mapcyclefiles.
If you forget to, the only way for it to appear on your server is a forced level change.

Step 6: Route your FastDL URL
tf2vintage/cfg/server.cfg has the following line in it:
sv_downloadurl ""					
This line is used to identify the fastdl for TF2V. It's usually kept in "http://<IP>:<PORT>/tf2vintage/" 
So for example, if you used the default port of 1236 and had an IP of 1.2.3.4, your command would look like the following:
sv_downloadurl http://1.2.3.4:1236/tf2vintage/	
Use Google or your search engine of choice to find your server's IP if you don't know it.