How do I place new content on a rotated or translated page?

Q: I am adding new Image Element to an existing PDF page. Some Pages
are rotated or croped in weird ways. In this Pages the Images are not
getting added at the intended location. How do we account for Page
Rotatation while adding new Image Element to this Pages?
A: You need to take into account the page rotation or crop-box offset.
Probably the simplest way is to use page.GetDefaultMatrix() as
described in the following articles:

What is the proper way to add new content to an existing (rotated/
cropped) PDF page:

Taking into account effect of page rotation when adding new content to
a page: