Can I use something that isn't a flat as background for text screen (using UMAPINFO)

[ViolentBeetle]

Wiki says I can.

PrBoom+ v 2.6 says I can't and displays "missing texture" red square.

Am I doing something wrong? I tried just refering to a graphic lump, tried adding it to PNAMES and TEXTURE1. Nothing.

[Worst]

According to the changelog, you'll need to update to PrBoom-Plus 2.6.1um for that feature to work.
 

[Kain D.]

Yes, you can.

 

You need to use interbackdrop = "x"  (where x is a lump name). The graphic lump isn't added to PNAMES and TEXTURE1.