Most of SEN users know how to use extra player colors (colors with number 16..254)

But the question is: what is the real reason of different colors on different PC?

I mean if color numbers are the same, and same map looks different on different PC.

And I mean not abstract reasons like "maybe RAM or VRAM or Operating System" - I want something like steps for defining - what color will be on map XXX and PC Y, if I know all needed information about this PC.

Does anyone know the real reason of different colors?

Extended player colours are 12 and above. 12-15 don't exist (it apparently does in some articles and in SCMDraft, but those are wrong).
You can't really predict the colour. It's a read overflow.

55 is black. Always black. I believe 56 or 57 is as well, but 55 is the one I'm positive of.
Also, you're probably already aware of this, but the colors don't always look the same on every tileset.

Yes - and this can easily be seen in PColor