MSR colors: why so many color versions for the MSR button?

I agree with you.  It would be easier to have just one hue for each color when it comes to a simple color exchange in your graphics editor (rather than getting down to pixel by pixel exchange).  It could be that when the graphics were rendered to .png format (or bmp when applicable), that the color actually changed due to the blending of surrounding shading.  When I started editing a new theme, I just stripped out the original colors and then redid them.  However, I did use different colors in each button state simply to better differentiate each state.  I then used those colors as a template for the various button sizes, for instance.  That way the color states were consistent throughout expect for special buttons like record, solo, etc. 
 
Kind regards,
 
tecknot

I use a "desaturate" tool in my graphics editor.  This will render colors as black and white.  In that format I can simply remove the gray hues (or not) and leave a black outline to work from.  If I leave the gray in I can easily change the color while using the variable shade  as a basis for color saturation (so I only change the gray area to color while leaving the black outlines for the bold color or an alternate color all together).
 
There is a free editor called GIMP here:  https://www.gimp.org/  Inkscape is a popular one too:  https://inkscape.org/en/  (excellent for accurate manipulation of objects).
 
Kind regards,
 
tecknot