How can I keep an image from moving when saving the file after cropping?

Question:

I needed to add trim marks to a PDF doc. I

(1) added trim marks (Print Production > Add Printer Marks);

(2) increased the page size to accommodate the trim marks (Edit PDF > Crop Pages > Change Page Size > Custom);

(3) saved the file.

The image and trim marks were centered before I saved the file. When I saved the file, the image and trim marks moved to the lower left.

This did not happen in Acrobat 9.

This did not happen with a document in portrait orientation, only a document in landscape orientation.

How can I keep the image from moving when saving the file?