Shekh, in your video demo of Master Blend you used a hover-over 'RGB picker' tool:
https://youtu.be/3PHcVBgqoHY
Where can that be found?
Also, re: your 'RGB Levels' filter. I see that the Gamma parameter is not implemented as yet. Do you plan to do so ? With that addition it would better serve as a '3-way' (Lift, Gamma, Gain) substitute for the Primary Color Wheels/Bars in Resolve.