(paraphrased) ...is it possible to mod the mod to remove all the images I do not like from ufopaedia?
Yes, for one reason or another we do not like some of the pictures and want alternate images
This goes basically for any mod that has extra sprites / pictures or whatever.
its EASY PEASY if you are just replacing, forget about .rul editing.
the short of it is just REPLACE the graphics by direct overwrite with YOUR altered files.
Longer explanation:
If you want a direct replacement of some of the graphics/pictures, locate where they are at,
on most mods just find the particular file usually in .png, .gif. format somewhere usually in the resource folder or maybe subdivided further resources/ufopedia ;
the point is find those picture(s) and note location.
One you've done that, open it up in an image editor to verify size etc, then do a "save as" into a DIFFERENT folder you want to edit from. Or you can just copy over the files you want to change.
Save as THE SAME EXACT NAME as the original file.
Three things to keep in mind
--the NAME and FILETYPE cannot change from the original
--the PIXEL DIMENSIONS cannot change from the original
--If there is an area designated for text, usually a blank, black area where the illustration does not continue, try to keep the modified graphic in that orientation, else-wise the mod's text may become unreadable against the background illustration.
Once you edited the files, keep them in your edit folder, but drag a copy of them into the mod folder where the mod's originals are and OVERWRITE.
When you run the game, because your modified files are exact name, format and size of the originals, your modified graphics will appear instead.
(keep track and place in bank vault this 'edit folder" where your altered files are at because you will need to copy them when/if the mod updates)
If the mod should update, install, as usual,
Check the mod's picture/graphic folder to see what changes there are and how they differ from the earlier version.
--if no or minimal changes, not just drag a copy of your modified files into the mod's graphic /picture folder and OVERWRITE.
--if there are changes, you may have to edit your modified picture files or the mod's graphic files in some way to accommodate the mod update to reflect the changes you want.