The first map, we want to add more to this soon, so it's not 100% finished.
Installation instructions: Move the BSP to the Half-Life 2 Episode 2 'Maps' folder, located in steam/steamapps/common/half-life 2/ep2/maps -- Then run HL2EP, open the console and type 'map hwndu' in the console.
It can be played in Garry's Mod to use in multiplayer, too, but, when I tested this the AI had some problems functioning in Garry's Mod.
We're open to suggestions, so if you'd like to contribute, feel free to enter our discord. Discord.gg