as i recall from years ago playing that game with deezire mod, it is something that was enabled by deezire, if u looking at finding out how, then i suggest u post it in deezire projects forum section, if the ? is why its there, is due to the fact its part of the mod.
In case I didn't make it clear, I meant the images are part of the map's INI, not part of a seperate mod program. I was playing RA2 on my friend's computer, which doesn't have any mods or even the XCC mixer on it, but he managed to DL an RA2 map with several TS units in it.