"Vertical adjust amount" for Graphic element not working in APP engine

I am setting the "Vertical adjust amount" property to an attribute for which the element is a graphic. The graphic is aligning correctly when publishing to PDF with FOSI engine, however, when publishing with APP engine it is not using the attribute to set the "Vertical adjust amount" and therefore, the graphic is appearing incorrectly. I have searched the documentation but there is no specific mention as in how to set the "vertical adjust amount" in APP. Any help will be appreciated.