Please note that the related action text message can be displayed only during the custom action execution. From what we know it is not possible to keep the action message through all the installation process.
If you want to simply use the same action text for all actions of the installation process, then you can achieve this by using our "Table Editor" feature available within an Enterprise project type. Just go to "Table Editor" and select the "ActionText" table. Then make sure all actions use the same "Description" text.
If you have any questions or doubts just let us know.