Hello Peter,
The UDP Messages are without the first slash (/), so the message is 'pb01/bu' using 'integer'
1) For OSC the message for an intensity fader is /pb01/in (float with range 0-1)
2) The feedback for a playback is ' /pb01/ac', the event you are seeing is probably for the button which is pressed (on) and let go (off)
I don't think the Colourpicker can be used like that, as it is sending actual colour values.
The Cuety is limited to its playbacks indeed. But you could just patch a single generic channel, add it to a playback near the end, record at full and use OSC to control the intensity.
For directly controlling DMX channels (and a lot more) we have the CueCore/QuadCore products.
Greetings,
Bootsy