In version 188.8.131.52, the following sequence results in the change to the entity name being lost.
- Type Ctrl+E and click in the model diagram to create an entity.
- Open Entity Properties dialog for the new entity.
- Change the name of the entity.
- Click on the Keys tab.
- Double click on Key1 to open the Key Properties dialog.
- Change the name of Key1.
- Click OK to exit the Key Properties dialog.
- Clock OK to exit the Entity Properties dialog.
- The change to the key name is preserved, but the change to the entity name is lost.
This problem occurs for existing entities too, but I can make the steps more precise by starting with a new entity.