Looks like WED doesn't like having too much textures: I've built two wads for the textures I had in the two folders and I can add one without any issue. However, when I try to load the second wad it gives me the error "No to all"
3D Gamestudio A8 Pro AMD FX 8350 4.00 Ghz 16GB RAM Gigabyte GeForce GTX 960 4GB