I decided to mash together a bunch of skyboxes together to make it go well with the desert textures used in the PS2 port of Half-Life. (The cliff textures are the default ones used in the PS2 port of Half-Life, I just took it upon myself to just slightly improve the quality of them)
I would highly recommend using this addon with this other addon: Gamebanana.com
There is nothing in your zip
Thank you for telling me, I fixed my mistake and the files should be in the zip folder :)
Nice
Thank you!