I've used these ActiveX Controls in a lot of my own programs and they are available for download with documentation. They can be installed in IDEs that support ActiveX such as Visual Studio, Delphi etc..
They are "invisible at runtime" ActiveX Controls. It amounts to a Delphi component that can be installed in any IDE that supports ActiveX, and dropped on a program form like a Delphi or VS control.
They are more designed to work with compiled code although there doesn't seem to be any problem with C# and event functioning. With AutoIt3 and Python events don't fire as expected probably due to the line by line execution of script.
One is a pretty Windows Message Dialog type.
The other is a "single instance" type with command tail transfer.
I first coded them in 2001 so I think I have most of the bugs out by now.
They are free for use at your own risk.