The graphics folder not exist in [ data\jdoom ] path. So, I've created it and I put the pic in this folder.
If you say in the root, you refer that the "graphics" folder must be in the root of the pk3??? or into the data folder? or jdoom folder ?The root of the zd-dhtp-20101225.pk3
So, I open other source pack from doomsday called jdui-all-20120223.pk3 and found into of it that the titlepic.png are into a [ data\jdoom\patches ] folder. So, I've decided to probe this pack without changes. And not work.
So, I rename the patches folder to graphics folder and I test.
What are the exact folder name, and where put it?