Zandronum

Alright so I have had Skulltag for a while when the guys who made it were still around and the website was working fine.

I have downloaded a custom WAD called Real Guns Hardcore (Basically MW2 in Doom) and wanted to run this wad through steam just so I can talk to my friends who play on Steam.

I have so far been unable to find out ways of being able to use custom wads through skulltag whilst running skulltag through steam. I can run Skulltag on its own through Steam fine, but just not being able to load custom wads through it whilst running the program through steam.

Is there any way to make this work?

Is don't think this is physically possible at the moment.
The closest you can do is find a zdoom or zandronum (such as QZDL, though I don't know if that works with Zandronum) launch utility and then fire that up through Steam.

LIAR! It's possible, right click on ST in Steam Library and select something called "Set launch parameters" and list here all your WADs.

Use -file command in launch options. Right click zandronum/st > launch options iirc