To demo my own levels, I use a registered Doom.wad. It is technically illegal to send a registered doom.wad to a game company, unless
ID gives permission. Has anyone out there tried to seek permission from the producers of DOOM to use their wads for promotional purposes?

I havent heard anyone doing this, but I would bet they probably really dont want to deal with this since they have other things to do, so wouldnt be interested in going through the process of allowing you to do it.

-Geoff