A mouse button action would be more intuitive and easier to use. Perhaps click to toggle the selected LED between the selected colour and off.
As an extra enhancement, how about having 2 currently selected colours, one linked to the left mouse button and one to the right mouse button, each with "click to toggle" the colour as above ?
Notes
Look at the illustrator UI as an example of what might be possible.
A mouse button action would be more intuitive and easier to use. Perhaps click to toggle the selected LED between the selected colour and off.
As an extra enhancement, how about having 2 currently selected colours, one linked to the left mouse button and one to the right mouse button, each with "click to toggle" the colour as above ?
Notes
Look at the illustrator UI as an example of what might be possible.