Happy to hear things are now working!
About the white intensity - please see RGBW not sending white parameter - #2 by Luka and RGBW not sending white parameter - #7 by Luka
To sum up: when you set a color using the red+green+blue combination via the RGB/HSL color picker or by selecting those modulations individually, Beam will automatically adjust the white intensity, when using a fixture profile that uses the RGBW colorspace, which is the case for the profile I made for your fixture.
While you then cannot control the white channel directly using the white keyword, the resulting colors will generally be more accurately represented this way.
If you still prefer to have direct manual control over the white channel, let me know and I will make a fixture profile that allows for that.