Currently, Emplode is just a "dumb terminal" that only works with the database stored inside the player. None of its database information is stored on the local PC.
This is actually an advantage. It means you can take the player to any PC and work on its music without having to worry about whether or not the local PC database is up-to-date. But it also means that you do have to connect to the player to get the database information before you can work on it.
Turning Emplode into a full offline bi-directional music organization system is in the long-term plans. Don't know how long this will take. But at the moment, it doesn't work that way.