Might be a little late for your project now, but I figured I'd answer the thread anyway.. Your answer is GOLDBOX, an add-on for GoldMine.
www.redstonesoftbase.com
It can perform recurring database tasks with GoldMine data and can hook into external data sources (anything with an ODBC) for two way updating.. It's a veritable swiss army knife of GoldMine data handling. And the developer is a nice guy too..