I am having issues with the Magnification API provided my Microsoft. This is an API that is written in C++ so to use it with C# you must use a series of .dll imports as described in this question.
My issue came after I had the magnification working. I was using my mouse to magnify a predefined area of the screen, the magnification was set in a rectangle, the rectangle filled a WinForm, I placed the form on top of my mouse (mouse in center of form), and the form would follow my mouse around the screen.
About 80% of the time, the app will launch with a black screen. I tried many different types of updates but can't find a fix. The magnification will not show up, it will only show a black screen. Nothing on the from will show up, only a black screen. In summary, only a black screen will show up, BECAUSE of the Magnification API.