Thank you for your feedback

The download errors are server related and not based on an error in the app.
It is only available in the store since some hours so it might not jet have been there when you tried it. The store description and the file itself might not have been added at the same time.
I expirienced this with other apps before.

I was a bit worried that the trial and full version might conflict, but could not test it beforehand. Also Nokia does not list any restrictions.