What features would you like to see in Pixelmator Pro?
And is the automatic feature in Catalina working for you? In general, when changing to Auto, Pixelmator Pro changed to both light and dark mode for me. But that's only when I set an exact time in Night Shift and went back to General settings to change appearance. When I set Night Shift to a specific time, the OS didn't switch appearance exactly at that time without me going to System Preferences and clicking Auto again so I couldn't check the feature organically... If this still isn't working, could you email us at email@example.com?