When opening the Damage Case Window, the damage case does not appear in its column and the file looks empty. What can I do?
Upon opening the .hmd file, I can see your model, compartments, loadcases, etc. You can just open the .hmd file directly and it will include all the information pertaining stability calculation.
Go to the global window and press CTRL A (since it was still empty when I opened your model), then add zones and so on... Please refer to the Stability Manual page 176 - Probabilistic Damage Principles for more information. Then at the Damage Case Window, type CTRL A - to input Damage Case Properties, and then you can see the DCase 1 appear.