PDFs don't show up in iPad App

I have an iPad 2 with Mendeley 2.1.2 and nearly all of my PDFs do not show up in my library. I see all my citations under All Documents. Nearly all the boxes are blank though--no arrow or book. Under Settings, I have turned on Sync on load and Sync attached files. The only exception to this is publications I have co-authored (My publications)--I was able to download and sync those.