Believe it or not my issues with getting gold in that challenge were way back at the bronze mark. For some reason there was a section where you hit a set of bones, drop down (and float) then hit another set and onto a bouncepad. It took me ages to get the timing down for some reason.
For the bit you're having issues with, tap jump as soon as you land on each of the platforms (you might need a few test runs to know the timing). All you need to do is tap jump at the right time - don't hold the button, and don't glide between the platforms. With the speed you get from the preceding bouncepads, you should hit each platform perfectly.As corny as it sounds, trust in the game mechanics for this one!
Oh, and be ready for a bouncepad onto a ledge at around 1000m - you need to jump as you hit the ledge and then immediately attack, otherwise you'll smack into a bonewall, killing your momentum and yourself!