High quality:  Use PNG as image format.

    Color depth:  Higher color depth gives a broader range of distinct colors and a larger file size. 

    Shrink filesize:  Optimize image files with lossless compression.  This option will slow down the build speed.

    Persistent names

    Checked:  Use a fixed filename for each image file.  The filename only changes when the image is changed or the add-in options are changed.  This is useful for synchronizing files to a web server.

    Unchecked:  Use numbered filename for image files, e.g.  img1.png, img2.png, etc.  The filename for an image may be changed when the Word document is changed.