The download thing can be strange sometimes as it can let you connect then will start downloading only after a /reconnect
If you have that file anywhere in the clients game or mod folder then it might not download at all (depending where it is as they paks/mods load in alphabetical order).
What I normally do is set fs_game to something and if I'm changing the contents then I just delete the entire folder.. which is the only guantareed way to force it to download. I've had old files there at times and sometimes doesnt download from the server.
I think it's similar to the issue where you can have media loaded in ram and the sounds and stuff stay even if you connect to another server

I highlighted this in the dev section.
Another thing you sometimes find, if you have a mod folder in the games location with the same name as the one in the home folder then the file will download twice. If the download repeats over and over again then it means the file being downloaded is different from the one that is referenced in the mod/game folder

Easy mistake to make