Perfect! Now everything works. Thank you!
I'll leave the mod as attachment.

Thank you for your help!
Your suggestion fixed the picture_on problem.
I just found that the layer index on picture_off starts from 1, so that is also fixed.

The icon still doesn't work and even looking at the data.raw I can't figure it out.
Now the code looks like this.

-- data-final-fixes.lua ...

Hi there. I have to say this is the first mod I'm writing.
The goal of the mod is to change the lamp textures and color mapping to improve readability of vanilla sev-seg displays.
While I had zero problems with color mapping and light intensities (which I only tuned), I can't find any solution to ...