When Stefania hands Adalinde the needle and thread, it's a straight needle. When she's later shown stitching up the corpse, it's a curved needle.
It makes no sense for the planks of the hayloft to be rotted. The rest of the barn is in good repair and these planks have been shielded from the weather by the roof. Generally, boards exposed to the rain and sun are the first ones to go.
The newspaper article states that the Austrian military police would investigate the death of Eric Renard. Obviously, this is wrong since this is not a military matter. Investigations would be performed by the Federal Police.