Other downloads have no problems, but this 10 GB download apparently has finished successfully as the media file is playing.
Using Tixati 2.12 64-bit on Windows 7 64-bit.

In Tixati GUI under Transfers>Bytes it says 10.163 of 10.556 M
  ,,         under Transfers>Progress it says 96%
  ,,         under Transfers>Progress>Peers all peers show fully red under Status/Incoming-Outgoing, so there is no traffic going on.

Other files are finishing and seeding without problems.

in the files tab a text file or sample file might be incomplete?

if the others are not full seeds you will not be able to finish the torrent.

I have just learned something I never considered.
The seeds are all stuck at 96%
Also I have run the media file and it will play but the content is damaged at big parts.
Thanks for the help, you pointed me to the right direction.