Custom screen textures

[VeeTHis]

Hello, I was wondering how I change the images shown on the Title Screen and Level Finish screen, like Contra Doom? For WAD editing purposes, I'm using Slade 3.

[scifista42]

Put custom graphics with dimensions 320 x 200 pixels into your wad, convert them to Graphic(Doom) format, and name them TITLEPIC and INTERPIC respectively.