Garmin has updated the free Windows-based simulators for the GTN/G500/G600/Txi products. Details here.
System Requirements
The following is required to install and operate the Garmin Aviation Trainer:
• 2.4GHz dual core processor or equivalent
• Windows 7 or later
• 10GB free hard disk space; 12-13GB during installation
• Microsoft DirectX 9.0 or later
• 256MB 3D accelerated graphics card or higher
• Screen resolution: 1280 x 1024 or higher recommended
Note that the trainer includes all the of updated user guides for the avionics and a guide to using the trainer itself.
BruceAir, LLC 
Hi Bruce — Great site and blog, thanks. It would be helpful to me if you could post the settings that you are currently using on your GTN750. Which user fields do you find are most useful on an auto pilot IFR flight/approach, just how your 750 is currently set up. There are a lot of adjustments that may make my interface/flights more intuitive. — Chris Currently in Pittsburgh, grew up in Hoquiam, WA playing on the driftwood along the edge of Bowerman Field, Cessna 172N with 2 G5’s, GTN750, GFC500.