This proved quite dificult, this .tex not only contains .png images pieces for buttons, overlays, text etc... but the position of every part, if the offset shift from the original it will freeze the game. So the block that contains the pieces position must have the same offset than the original.
So I created a shell from %PNG magic and IEND, thanks to
@JRoad for IEND magic, filled with zeroes, edited the png and pasted it to my created shell. It has the exact same file size as the original as result.
And worked in the end.
It
should work with all the games, but I only tested with cotton2.