For your convenience, here are the compiled rules we discussed regarding this issue.  Feel free to make a post here to remind everyone of one of our rule clarifications if you want.


Fatigue Points:

You have a number of FP equal to your constitution score.

You automatically have a -1 fatigue point for every 1/4 of your hit points that are lost (semi-permanent until hit points restored).

Fatigue points are gained back as follows:

Full rest for 1 round gains 1 fatigue point back.

Walking for 2 rounds gains 1 fatigue point back.

Fatigue point costs are as follows:

Walking: 0 fatigue points per round.

Jogging: 1 fatigue point per round.  (You can jog at twice your movement rate (12 equals 240 yards per round).)

Running:
--Speed: 3x normal = 2 fatigue points per round.
--Speed: 4x normal = 3 fatigue points per round.
--Speed: 5x normal = 4 fatigue points per round.

If fatigue points reach 0, the character may continue at a jogging rate by making a CON check each round -1 cumulative modifier.  Though a character may continue jogging, FP can never go below -4.  Failure of this check means the character walks for the selected round without gaining back fatigue points.

These wildcard actions are just for fun if you want to try them:

WILDCARDS

Running adjustments.  Announce the following if you want to try them BUT DO NOT ROLL FOR THEM.

Each of the following must be rolled for BY ROUND unless noted otherwise.

Give the score you must beat and DM will roll:

SPRINT
(Run fast without penalty.)

Make a 1/2 DEX plus 1/2 FP roll.

SUCCESS: You can add 100 yards/round for 1d4 rounds to your speed.
FAILURE: Trip/lose balance/twist ankle: Subtract 150 yards/round.
CRITICAL SUCCESS: Add 1 speed factor to your current speed for 1d4 rounds (2x base speed would go to 3x base speed, etc.)
CRITICAL FAILURE: You have twisted your ankle or hurt yourself. Must remain still for 1d4 rounds or receive at least a cure light wounds.

PACING
(Pace a slower companion -- for jogging only.)

Make a 1/2 STR plus 1/2 WIS roll.

SUCCESS:  You pace for 1d4 rounds with only losing half normal fatigue points.
FAILURE:  You trip up and fall.  You have one round of 0 movement.
CRITICAL SUCCESS:  Same as success but you lose no fatigue points.
CRITICAL FAILURE:  Same as with Sprint.

RUN BACKWARDS
(Go at walking speed backwards without penalty, allowing firing of arrows or other attacks.)

Make a 1/2 DEX check plus 1/2 FP roll.

SUCCESS:  You may fire arrows and move at your walking pace backwards.
FAILURE: You trip and fall.  (Same as pacing.)
CRITICAL SUCCESS:  Same as success but you can move at your jogging speed.
CRITICAL FAILURE:  Same as Sprint.

Fatigue Avoidance:
(Reduce costs of fatigue when running.)

Make a 1/2 STR plus a 1/2 DEX roll:

SUCCESS:  You only lose 1 less fatigue point when running (1, 2, and 3 instead of 2, 3, and 4.)
FAILURE:  You must drop back 1 speed factor for two rounds.
CRITICAL SUCCESS: The above lasts for 1d4+1 rounds.
CRITICAL FAILURE: Drop to at least a jog; no more running until you have revived all of your FP back.


The Running Rule:

RUNNING

This basic rule remains unchanged except where boldface:

If he rolls a successful Strength check, he can move at three times his normal rate; if he rolls a Strength check with a -4 penalty, he can quadruple his normal rate; if he rolls a Strength check with a -8 penalty, he can quintuple his normal rate.
(Choose which rate you are trying to reach maximum, and then the roll will determine which rank below that you attained.)

Failing a Strength check means only that the character cannot increase his speed to the level he was trying to reach, but he can keep running at the pace he was at before the failed Strength check (or at the highest level succeeded on the roll of the dice). Once a character fails a Strength check to reach a level of running, he cannot try to reach that level again until he has at least 3/4 of his fatigue points.

Continued running requires a Constitution check every round, with penalties that depend on how long and how fast the character has been running. There is a -1 penalty for each round of running at triple speed, a -2 penalty for each round of running at quadruple speed, and a -3 penalty for each round of running at quintuple speed (these penalties are cumulative).  If the check is passed, the character can continue at that speed for the next round. If the check is failed, the character has exhausted himself and must stop running. The character must rest for:

2d4 rounds plus/minus any constitution modifier.


Fallback/Mixed Speeds:
I DELETED THIS BECAUSE THE FATIGUE POINT SYSTEM SHOULD ACCOMMODATE THIS.

This message was last edited by the GM at 23:01, Mon 23 May 2011.

I was asked about how the Endurance and Running NWP affect these rules, so here goes:

Endurance: Make a proficiency roll.  If successful, at the end of each turn, he gets back half of the FP he spent during that turn (rounded down).  You announce the use of this ability after the Turn is over and before posting a move for the next Turn.  If proficiency roll fails, he does not get the bonus but is at a -1 modifier (cumulative) on saving throws and combat for the turn after failing to make the endurance check.

Running: When he actively announces he is using it before the next turn:

First, decide which of these two options are being used and make a proficiency check.  If successful:

1) He will get to go his jogging speed plus his walking speed at a cost of 1 FP per round.

2) He may also choose to go 6x his walking speed in a very fast run at a cost of only 4 FP per round if he makes a successful STR check at a -10 penalty (and according to the rest of the running rules).

BUT

He will suffer -1 modifier (cumulative) for the rest of that turn and one additional turn for each turn he spends using his running skill for rolls related to saving throws and combat.

If proficiency check failed:

An extra 1d4 FP are lost and he suffers the negative effect described above without any benefits of the Running proficiency.