Originally Posted by TerryM
Does anyone know if and how the software maybe run on Mac please?
You will have way less frustration if you just go buy a cheap used USB PC. That's what I did, and I'm happy for it. I picked up an eMachines box and a KVM switch that let's me use my keyboard/video/mouse from my mac on the PC and I was good to go.
I also have a 276C, and even the old eMachines loads routes and waypoints in seconds via USB. You should be able to find a suitable machine for not much more than the cost of VPC software.