I am using Windows 10 and Magix's MP3 deluxe 19. To me this is an important point to clarify in the help files. Anytime one is deleting anything,much less an entire database, one wants to be sure just what is happening when that delete key is used. Thank you.
Looking at the date you posted this you have probably found your answer, but if any one else is looking for the answer. I regularly delete my old projects and can say it only deletes projects in its own folder.