Starting with macOS 10.13 (High Sierra), Apple has added a new security feature that prevents third-party kernel extensions from loading without specific user authorization. For more information about this from Apple, please see TN2459.
To install the driver completely, first open the Lynx_OSX.pkg that was downloaded from the www.lynxstudio.com web site. After the driver installs, you may receive a message that a Kernel Extension has been blocked. Either way, go into the Security & Privacy of the Systems Preferences pane, and click "Allow" for the Lynx Studio Technology extension. Once you restart your system the driver should load properly.