MySQL as target connection in DTS package will not perform update

We are performing an Update/Insert step from Progress (Source) to MySQL Community (Target). We are using the free MySQL/ODBC Connector that comes with the Community edition. When I perform a test job within workbench, the step results for existing data in the target system is correctly showing 'Update' but when I run the job it attempts to 'Insert'. There is no reason why it should do an insert when it is existing data. Support told me that it could be an issue with the free MySQL driver and we need to upgrade to MySQL Standard in order to use the Scribe supported MySQL driver and that should resolve the issue.


Before I go down that road I was wondering if anyone else has experienced this also and has any advice or was able to resolve this? Could it be a setting on the MySQL end I'm not seeing? Just want to make sure I've researched all options before I upgrade.