I don't see your problem. Just send the data to the according address of your light.
Maybe you do not understand the addressing of DMX lights?
You need to configure an individual start channel (address) for every light with a spacing of at least the number of channels your light support. E.g. your RBGW light is set to 4-channel-mode and its start channel is set to 1, then it listen to the channel 1, 2, 3 and 4. The next light can have the start channel 5 and so on. Some more complex lights like moving heads can have more than 30 channels. It is possible to have up to 512 channels per physical bus (called DMX universe)
You may set several identical lights to the same address but then they all do the same.
Also very important: The last light in the bus should have a terminator plug/resistor. It may work without but often a missing terminator cause strange effects on the DMX bus.