Problem with the recovery tool on BaccS 5.0.4 freelance edition

My main PC died. Luckily I do almost every day a Backup of my data :). Now I'm sitting on my second PC and installed the new SDL version. All seems to be working like it should, but I can't restore my data using the restore tool in the BaccS 5.0.4 freelance edition. I get no response or warning from the software.

  1. I click on the Restore backup button.
  2. there is the confirmation "Please save all changes before...", I click on Yes
  3. after that I can choose the file (.bak) for the recovery, I click on Open
  4. and then... nothing happens!

How can I fix this?

Thank you.