So it happens, that I wanted to overwrite the texture “tdc01_flrcrack”, which is part of tdc01 (crypt), tile tdc01_a01_01 (standard bio tileset)
I took the texture (hires version), converted it to tga and painted my black hole on it. Then I put the resulting tga into the top hak of my module. Result: it doesn’t work, the tile is shown with the original texture.
If I put the very same tga-file into override, it works as expected. The new texture appears on the tile.
I forgot the content priority order, and the old pages where this was written are lost or updated to reflect how it work in EE which changed it I believe.
But check if you don’t have the texture in patch-hak, it could probably have higher priority. This is probably one of those “if there is dds and tga then shit happens” sort of thing though. So maybe convert to dds and try like that?