The TD is not designed to work in this way. The software loads the database when it starts and retains it in memory, and rewrites it as necessary. So in your scenario, each instance of the software will be working with its own copy of the database, and changes to one will not be seen by the others. This also means the last one wins, which basically means the last instance to write the database will be the one that is ultimately saved, as it will overwrite any changes made by the other instances.