Color/Tint Texture

I have a load of these damage alpha type textures (black and white images) - I have them blended to add damage lines/cracks etc on top of my base materials but, as you can see they appear white

  1. I am trying to work out what nodes I need to add to adjust/tint just the colours of the cracks? Have tried 'add’ing to with color param but it colors the whole map, tried ‘multiplying by’ but it only works with lighter colors, not with darker colors (which I really need)

A good way, would be to increase the albedo power in the cracks. You can do that by using the mask to lerp between the two different albedo values.