If you use a custom name for your texture you won't need to back up the included textures.
I call mine Test-7c1 and so on.
So this is the 7c_1 template
This is what part is what
If you use this second image the lettering will show up on the Turm.
Notice that all Grey areas have been changed to the purpleish.
That cause those areas to not render.
The Game looks at the upper left pixel and uses that color as the transparent color.
So it can be any color you like.
So here's what it looks like in Game
