Is there an intrinsic colour picker you can call at runtime or do you have to make your own?
Found what I needed. it is cryptically named ‘selectcolor’
I know. Those Xojo engineers. Where did they ever come up with “selectcolor” for a control built to select a color. The fiends! 
Logical naming conventions??Thats all we need. These guys would never get a job in the Government.
I wish SelectColor had a parameter to optionally enable the user to set the alpha as well. Some Mac apps at least seem to be able to use the system colorpicker with an Alpha slider… Don’t know if that is true for Windows as well… But in any case it would be nice.
The system color picker is completely async and actually works completely differently.
It basically sends a set color message to the front window