The Visualizer can support multi-color sets using a sub-channel type. Only the String type can use multi-color.
To create a multi-color channel, create a string fixture and assign a channel to it. In the "Special Type", select "Multi", and then select the total number of physical colors this channel will represent. After selecting the number, one or more color boxes will appear to allow you to set the color.
By specifying Multicolor, you can assign up to five different colors to the channel. You don't individually control these colors. When the channel is on, then all (1-5) of those bulbs are on.
Fixtures can have multiple multi-color subtypes. In theory, you can create a fixture with 80 separate colors (16 controlled in groups of 5), but there is a lot of overhead when creating multi-color bulbs, and so that is not recommended. The multi-color sub-type can also be used to simulate multi-channel rope light where there is more than one bulb per circuit.
Multi-Color settings