For those of you interested 
This project is progressing quite well. I have designer templates for iOS, macOS and tvOS
for macOS “most” of the controls are drawn by the OS, so they will meet any user/Apple changes, and work with Light/Dark. a few (including most all for iOS) do require custom drawing routines, as macOS doesn’t have the drawing code for those.
Here is a snapshot of the designer in macOS mode. There are still a few controls missing (such as Listbox 
). Notice the switch in the upper right corner… that is in fact a native control for both iOS and macOS (Xojo just hasn’t included it)
the controls for iOS still need work, but those are the ones that are mostly manually drawn