I tried the example XAML Subclasses. Pretty neat. I ran into a peculiar bug: when you try to read i.e. the value of the XAMLSlider in some event the compiler gives the ‘Cannot get this property’s value XAMLSlider1.Value.ToString’. The component itself can read the value of course.
Issue an Issue Report. https://xojo.com/issues
I think something like this is missing in the Value-Get-Method of the XAMLSlider-Class: