I get this error message whenever I try to initialize any Gn* object. Specifically for GnManager, I am using the path that contains the gnsdk_csharp_marshal.lib file from the SDK and a filename that contains the license string specified for my application in its entirety (beginning with "-- BEGIN LICENSE" and ending with "--\r\n"). The license string file is in the same directory my application is running from.

My instantiation therefore looks like so:

GnManager manager = new GnManager(Directory.GetCurrentDirectory()+"\\lib", "license.txt", GnLicenseInputMode.kLicenseInputModeFilename);

My mistake, I made the assumption that the libraries included in the wrapper projects included the required portions of the SDK. Copying the dlls and libs from the full SDK into the same folder as gnsdk_csharp_marshal.lib did the trick.

Unfortunately even when working it misidentifies too many tracks to be reliable.