Cacoman

I'm using Doom Builder in Doom 2 "mode". If you go to Export... and check file extensions you'll find the .obj file format but, if you click "Save", it doesn't save anything.

Hello everyone, I'm an italian Cacoman so my english isn't very good but i hope you can understand me. I need to export a map in .OBJ file format and i see there is this kind of opportunity in the export menu, but when i try to do this no file is saved. Do you know how to solve this problem?