I’ve updated the download link with a switch function for using the standard colour cycle without a mask, just set the “Has neon mask” variable in the instance and you’re good to go.
As for syncronising the colour you need to set the tiling variable which I’ve also added into the material now, by default it’s set to 0.0001 just increase it to get a shorter spectrum (More gradient like you have now) or decrease it to make it fit to your current mesh.
Explination - The reason you need to set the tile is because I’m not calculating a gradient spectrum, Im using a standard spectrum png to allow people to make their own spectrums easily and have it cycle through their own choice of colours.
–EDIT: I’ve added a video above to explain how each material works and how to set the values to how you want them.