ver 3.2 has example to show how to add bitmap anotations.
just click "Stamp" button, and then drag on screen.
AddAnnotBitmap need conditions:
1. Document.SetCache() invoked, and only once for each Document, and do not share same cache file name for different Documents at one time.
2. Bitmap must be RGBA32 pixel format.
3. professional or premium license actived.