What are these rules?
Essentially, these rules provide a mechanical framework for determining what it takes for the PCs to travel from point A to point B and what difficulties arise on the journey.
How does it work?
When the players want to travel somewhere a significant distance away, plot a course on the map and divide it into a certain number of sections marked by Checkpoints. At each Checkpoint, the players must make a roll to determine how easily they make it to their destination. On a success, their journey continues without incident. On a failure, their journey proceeds, but they suffer a Complication along the way.
A Complication can be something such as an environmental hazard (falling rocks, rushing water, collapsing bridge) or combat (with animals, bandits, or even Feondas). Environmental hazards create a tense scene in which one PC is imperiled and will suffer some injury unless he can skillfully avoid the danger or be rescued by a friend.
Additionally, these rules contain additional rules for using different skills while traveling. Characters can hunt for food, try to find medicinal plants, and Varigals can use their unique talents to get the party to their destination safely and even faster.
What kind of atmosphere do these rules encourage?
The world of Esteren is a shadowy wilderness fraught with danger, and with these rules you can reflect this reality in your game. Traveling overland is risky, and novice adventurers are likely to suffer injury. These rules also help foster a team atmosphere, as PCs will be placed into dangerous situations where they need to rely on their party members to keep them safe.
What still needs to be done?
- The specifics of determining length of travel time and # of Checkpoints
New environmental hazards
Specifics on using additional skills while traveling
How to determine Difficulty Threshold for Complications and Rescues
Fine-tuning of various elements
I homebrewed these rules for my campaign specifically because I want the party to do a lot of traveling, and I wanted a way to make long journeys interesting both mechanically and narratively (providing danger and survival), without having to plan various encounters along the road in advance, or rely on my (dubious!) ability to come up with various interesting encounters on the fly.
There's certainly an element of simulationism in the rules, though. Ideally, the GL will heavily narrate the journey and Complications, and the players will take the opportunity to RP their actions as they come up. Much like with Skill Challenges, the whole endeavor becomes pointless if it devolves into rote dice rolling. "Okay, roll a Travel check. You passed? Okay, roll another one. Passed again? Cool, roll another one. You failed? All right, uh, a bridge collapses while you're walking over it. Roll me Acrobatics or Climbing..." 
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