Well, it works, but I immediately noticed 2 things that could be fixed.
First, use a light_environment entity to add lighting to your map. I'm assuming you didn't change the default skybox (sky_tf2_04) because you can't see it anyway (you can change it by going to Map > Map Properties > Skybox Texture Name). So, you can fill in the values of the light_environment using the ones for sky_tf2_04 on
this page. This will make your map very dark because it's all indoors, but adding light entities inside the room will light up the space. Not only will this give your map a more complete look, it will also agree with servers better, because fullbright (no lighting) maps can cause issues with any maps that come after it.
Second, the pit in between the colored brushes is some sort of leak or nodraw hole. Make sure you seal the bottom of that pit with another brush that isn't nodraw-textured.