If I were to add a light in my 1 bit game would that break the rules as the light creates different shades of the colors I have in game, or would that be allowed?

I believe it would break the rule. There's something in the rules about alpha channel but not sure it applies here. My rule of thumb for this jam is never render more than 2 colors in any given frame.

WORD of advice, super primitive lighting like making non lit up areas black may help?

but what if I placed a let's say black panel with 200 alpha channel on top of some coloured panel with 255 alpha, that will create a new colour, will that count as a new colour or Is it acceptable?