Missing umlauts | Box when no options are selected

I have imported the following test PDF:
https://dl.dropboxusercontent.com/u/51485107/PDF_X3_D.pdf

Unfortunately on some texts the umlauts (äöü) are missing. Please see my example here:
http://dev.mst-russia.com/capabilities/#page/14

On the top of the page there should be:
“Die häufigsten Probleme …”, instead it’s only “Die h ufigsten Probleme …” the ä is missing.

My second problem is, when all options are off, there is an ugly box showing on the top right of the file:

TIA and kind regards
René