The way this is written like a real new hire orientation package is very charming. One thing I'm wondering though is that The GM is presented as The Handler in the fiction and is characterized as an external resource working to help the Rangers accomplish their goals. This clashes with the narrative built into the rolling and allocating successes system, where Handler successes count as harm to player characters. Perhaps for this game, flip the framework and write it so that Handler failures result in harm to the player characters, rather than their successes. That might keep the narrative framework a little more consistent.
I also feel like there's an opportunity to condense the Capabilities a bit. I see both Calm and Convince are distinguished. I can see why Calm is such a useful capability as many of the adversaries are wild animals. I do only see three preset encounters with sapient NPCs though that I think Convince would typically be used in the place of Calm. It feels to me that Calm could probably be used for all social encounters and you could potentially drop Convince entirely.
I like the Energy -> heart -> injury system in concept, but I feel like it might be hard to track as you have 5 different events triggering energy loss, that then start to trigger heart loss when you're out of energy. Then you have 4 other ways to lose heart on top of that, plus the 4 ways to regain heart. I'm not saying the idea should be scrapped, but I do think maybe it needs to be on the character sheet to help remind players when to mark them. I do also like the pressure to get rest and how you make that challenging if locations have active threats.
I think I could use more guidance on where to start and how to move through areas. It seems like you start in the River Valley and pick one of two paths to the Alpine Valley, but I'm not sure if I'm reading the map right.