You might want to check with local authorities---it might be illegal to do this to your car windows, since it would permanently obstruct your vision...
you can use window/glass paint on the etched parts after the etching has dried
I'm not sure that window / glass paint is dishwasher safe? But if you find a brand that is, post the name of it here. I've not found one that's dishwasher safe...
"Hi, I didn't read through the 9 pages, but I didn;t see photos of Colored Etching cream. can you add food coloring or something, and if this has already been addressed, ignore this and Make me read through the pages to find it, I deserve it. "
---Well, you can use colored glass to start with. The etching cream is a caustic substance that permanently eats away the surface of the glass, "etching" it chemically. It's the equivalent of chemical sandpaper. So no, adding food coloring to the etching cream wouldn't change the color of the glass. The only thing that would give you "colored glass results" would be to start with colored glass in the first place. My friend and I did some blue glass recently and it turned out beautifully.