Can not config Doom Builder!! AIEEE!

For some reason i cant configure Doom builder correctly, ive pointed it to my doom2 iwad and everything SEEMS to be alright but when i open up a map it just shows me a jumble of lines, verticies, and incorrect textures! on a previous map i made for ST it said that all the textures i used were missing even though they were correct and had the right name put in, help plz anyone?!

Did you remember to add either your project wad or texture wad every time you load the map up? Otherwise added textures don't work.