Well, I mean, I was really asking if someone had fiddled with it for their own use (and improved it), and might be willing to share.
What Sorbus did with his fork is to discard all syntax highlighting except for Harlowe's. So, it's really only useful for the people that use that format.
In my understanding, you'd need to get the language dev package for sublime, in order to possibly work with these language files, or publish a new version based on your edits.
And I might go do that at some point, since it's obvious the syntax is in need of updating, given the advances of sugarcube.
Here's a pic of how it currently messes up:
https://ibb.co/iVDOsG
So, you can clearly see that it has issues with <</if>>? I think that's because it rather expects the old way of terminating <<if>> statements, whatever that was. <<end-if>>? Something like that.
And from the pic, you can see how it breaks, by the preview of the file on the right. Becomes overloaded? Confused. I dunno. But, I'm pretty sure the language syntax needs some correction to resolve it.