The replication model is referred to in the help manual.
If your web server is remote, and/or bandwidth was severely constrained between your office and your web server, you should probably use the replication model to overcome this. This means that you'd have a TntMPD.DataServer database on your web server which is replicated locally. This would allow you to connect to your donation system database locally (which you could never do from your remote web server) and pump donations into your local TntMPD.DataServer database. Then you could synchronize those changes with the TntMPD.DataServer database on your web server only sending and receiving changes (so it's very efficient with bandwidth).
If your web server is local (in-house) you probably shouldn't use the replication model. You probably have a computer somewhere in your office which can run TntMPD.DataServer and have access to both your donation system database and the TntMPD.DataServer SQL Server database. Your web server itself might, in fact, have this capability. So in this case, there's no need to have a seperate database on your web server, and another replicated database somewhere else in your office.