I use the Microsoft.Office.Interop.PowerPoint API to embed PPT into a desktop program, and encounter the following problems:
The PPT will appear first and then be embedded in the program. Can it be avoided?
Use PpSlideShowType.ppShowTypeWindow mode to display and open the pen, sometimes the pen cannot be used: can't draw a line, line will be displayed after draw end, the line drawing is not complete after the window is enlarged and so on.

When the PPT has been opened directly, Microsoft.Office.Interop.PowerPoint.Application app = new Microsoft.Office.Interop.PowerPoint.Application(); will throw an exception.

Is there any way to solve these problems? Thank you!