Hasta La Motion!

I’m trying to colour remap a greyscale render and want to have a number of points along each r,g, and b curve in a ColorLookup node, their X position will match between each colour curve and will be controlled by a 0-1 ranger slider, while their Y position will be controlled by a user picked colour.

So if point1’s X slider is set to 0.25, and the colour picked is a pure red, and point2’s slider is 0.75 and is a pure green, the curve would be

red {curve x0.25 1.0 x0.75 0.0}
green {curve x0.25 0.0 x0.75 1.0}
blue {curve x0.25 0.0 x0.75 0.0}

Any ideas on the kind of expression I’d need for this? I can’t seem to control the placement of curve points at all, only define an overall curve with an expression like pow(x,2).

I’m VERY new to NUKE so any help would be greatly appreciated. I’m trying to replicated a node someone made in Fusion that did a gradient colour remap.