How do I add games such as doom mods to the "ports" section?

I want to add two separate titles, the Doom total conversion “Sonic Robo Blast 2,” and the Quake total conversion " X-Men: The Ravages of Apocalypse" to my “Ports” category since it came with ports of both Doom and Quake. I tried copy and pasting the Sonic files in the Doom mods sub folder, and creating a new folder for X-men, but neither of these seemed to work. How can I do this?

To be clear, I am trying to get one icon for Doom, and another the total conversion with its separate artwork.