I forgot to react on your other questions:
i still don't understand where STX learns about "DSN=...." or "DRIVER=...".
ODBC is a protocol for data access. All you need to do is define an ODBC datasource in windows. At that level you also specify the DNS and the driver, but you also give it a logical name, e.g. the 'stxtestdb' in your code. STX supports ODBC. All you have to do is specify the logical name and logon stuff when you connect. The company or group that supplied the database generally also delivers an ODBC compliant driver to access this database.
Good luck,
Jan