@demonimp
Remember the effort required to learn about TT and it's navcores, maps and their features etc? Well, unfortunately, ya gonna have to do it all again with Garmin 'coz as you've already worked out they're different. You might have skipped looking into the very first listing in the initial post here [Only registered and activated users can see links. ]. It's far more than just downloading tips, just start there and read the linked threads as necessary.
PS: I'm rarely kind and not a sole but i often flounder, close enough i reckon ....