Pakrat isn't working for one of my maps.

[Pikmin 23]

I've recently started work on another map, which uses a large amount of custom textures. However, I can't pakrat files into this map. Pakrat just stops, the last line in console being "Pak lump entries: 0". Does anyone know what may cause this? It works fine for my other maps.

 

[Pikmin 23]

Nevermind, I've solved it. Turns out that pakrat needs built cubemaps to work.