Gateway requires MySQL to be installed globally
Currently the MySQL Connector requires you to install a specific version of the MySQL .Net Connector (I believe 6.5.5) in the GAC. If the server already has other apps on it with a different version of the driver this will cause the other apps to fail. The MySQL DLL should be part of the Gateway install so it will be accessed locally (same folder as executable), therefore not causing a conflict with other MySQL Apps. Or fix it so if you have newer version installed in the GAC it can use it.