Sorry. I'm hanother issue. I was playing Mines of Titan on Works of the Masters in GZDoom with this load order: Beautiful_Doom_716.pk3, doom_complete.pk3, masters.pk3. When I got to the exit of Mines of Titan, I got an error.
EDIT: Apparently there are discrepancies with Beautiful Doom. Worked perfectly fine when I took it off the load.