The OP's issue with downloading the trip is unfortunately a case of not understanding how the new Tripmaker software works.
When you generate a trip online and tell it to send to GPS, it generates a code phrase of several words. That phrase is NOT entered in the online screen. It's used in the docking software. You click on the Tripmaker icon in the docking software, enter the phrase you were given online, and it retrieves the trip and downloads it to the GPS. Worked for me.
Steps are clearly spelled out in the online guide.