(v4.0 H1) Restoring Control Panel Pages/Links(1507-10 22H2)

Set Default Programs page from Default Programs (sud.dll) (Removed in Windows 10 1709-1803) is the only control panel page from windows 8 , 8.1 era that cannot be restored and cannot be remade completely and even there is no good replacement application for it even I could not remake it functionalities completely "Set default app or program for file types by app." feature was the only thing that I could remake it , but it is not perfect either because some of current defaults would not show in list view (you will have exact same issue in default programs editor)
-Make an app or a program the default for multiple file types or protocols it can open at once.

Microsoft removed the calls sud.dll makes from shell32 iirc. Those calls or functions were for loading the program icons and names and send them to sud.dll. The reason the first child page was empty was this. I remember talking with Aubrey about this too.

Can you not copy an old shell32.dll rename to something different then hex-edit sud.dll to reflect of the other shell32.dll

I am encountering several problems with your program.
However, I seem to have installed the .NET components.
On the other hand, I don't see all the programs in the list, but the list increases in size with each update.
Finally, I can't change the settings. When I click on a file type, I just get an explorer property window that appears for 0.5 seconds, then disappears. This may be related to the fact that I'm using OpenWithEnchanced instead of the default dialog.