Anyway, I don't know if I answered you questions or not

I hope I did.
You sure did This seems like a very fun setup to work on. I even brewed my mate, so st just got serious.
I'll write a bunch of stuff that's more or less ready to use - that's not because I want to impose them on you, but it's a lot easier for me to just show an example of what I mean instead of explaining it (it's something I'm really bad at).
Just before the race begins, have the characters sign a piece of paper - a scroll, handed from one to another among those who are starting (point of this being, that PC's don't get suspicious about it - everyone is doing it).
If for some reason they do inspect the document closely - it's a liability release form. It states that they will not pursue in any way (legal, martial, arcane or divine) organizers of this triathlon for any deaths and/or permanent losses of health. Organizers are will not refund costs of any spells necessary to restore competitors to state (or plane) in which they started the race.
And now is the time to make them know what they stepped into.
Because of some past... incidents... We remind all of you some basic rules of this race. There is no killing, successful or otherwise. You are not to use any lethal weapon, artificial or natural. All dragonborns are reminded that belching with killing intent is also prohibited. Of course saps, small batons and clubs, chloroform sheets and such are allowed, just as fists - but no claws! Don't worry, this only applies to your fellow competitors. Any threats we set up for your amusement on the track - you can (and in fact should) respond to with full force available.
By killing or using lethal force against any other competitors you succeed your final place to him and will be charged with 800 gp's Griever Fee(Raise Dead cost + additional fee's). So if you finish first after slashing at someone, he get's 1st place, you're last, and have to pay to him or the widow, capiche?
Race will start when I say start.
(Any natives will start running when he says "start" for the first time (the bolded one). It's a long running rule and is not considered a false start). If they start immediately after, that should count as only a few feet, it's meant just to signal that it's not going to be a fairplay thing.
This is an idea for mesh between a skill challenge and a non-lethal encounter. I'm afraid that I have only rudimentary understanding of 4e rules, especially with erratas, so I'll write how I'd do this by adding quickie house-rules. If there's some better way to do this, please mention this.
The idea revolves around using non-lethal damage. Non-lethal weapons have lower damage output and attack bonuses. When a character looses all of his HP's to non-lethal damage, he falls unconscious.
[sblock]Our PC's meet Gary at GenCon and want him to DM a game for them. He doesn't want to, so they have to subdue him. Of course they cannot kill him. He has total of 120 hp's. PC's count the damage. He has 70 hp's (50 dealt) and still isn't bloodied. Then he gets hit which drops him to 45 hp's (75 dealt), and is now bloodied. PC's know he has somewhere between 100-150 hp's, and thus possibly only 25 remaining. Not risking any mishaps, they start using only their fists,staffs and hilt of a sword and deal non-lethal damage only. 46 points of damage later - Gary falls unconscious(but is alive).[/sblock]
I don't know how non-lethal works in 4e, so I'll add some quick solution to this. it's in spoiler blocks, so it doesn't make this post too unclear.[sblock]Any attack deals either [W](half for blunt weapons, custom for others) or attribute damage only , but retain additional effects that come from attributes. For example:
Attack Name (level)
Hit: 1[W] + strength modifier damage.
Effect: You push the target amount of squares equal to your wisdom modifier.
You use sap, a perfect weapon for mugging people, and only 14 str, and you decide to use [W] for damage. You have +2 wisdom, so you push your target 2 squares.
Magic attacks, especially elemental would deal only lethal damage.
This is meant to allow players to use their powers effect's, not to beat everyone senseless, so it'd be a nuisance only. If they continue to beat someone however, you can add some more things - ie, when "bloodied" for non-lethal damage (let's call it "bruised") you gain weakened or dazed condition (fort saves).[/sblock]
Additionally, along the set will be placed dummies and wandering critters. Against them, you can go all out with lethal damage. This is because there are powers that allow strange movement outside of acrobatics skill checks, but they often use damage and weapons dealing only lethal damage.
For triathlon I'd suggest:
1. Main - cross country running
2. Swimming (and for those who used water walk ritual it's still a sprint, thee hee).
3. ? Maybe it could be riding horses/ other mounts? This way, 1st part would be a struggle mostly against surroundings, as it will be almost always more beneficial to move twice, or move and take action than attack others. On mount on the other hand, you can take your sweet time to attack others.
1 - make a track, and add goodies:
- A 60 feet tunnel, in which small creatures can run with normal speed, while medium have to crawl or be crouched (let's give a bonus to those who decided to make a short medium char instead of maxing his height for encumbrance). You could make it a simple maze, in which dungeoneering skill check would allow to immediately know the right way (they go where the airflow goes).
- A cliff to climb (athletics), or possibly find a way around (nature)
- Perception checks along the way to spot shortcuts
- Insight/streetwise to realize they're somewhere where refs cannot spot them and so they can abuse the rules
- Nature to realize that a bear is stalking the group, and higher check to realize he is attracted to food rations group has with them. (streetwise/thievery to plant some food in other competitors backpack/pouch to make the bear go after them).
- A long and narrow path at riverside with steep bank. Characters can be thrown into the river with a number of powers (ie bull rushing). If they fall, they take some falling damage and have to swim to the bank and climb back up. You can set up some traps here (like Malaysian hawk*) to force characters down. Log would go at height of 1.2-1.3 meter, hence missing any and all small characters
- characters could make own traps if they gain advantage at race, which frankly can pay off at stage 2 if they don't have water walk ritual ready. They can also choose to manually reset any traps they activated so that other competitors will fall prey to them.
And so on...
I'm out of hot water, so that's that for now. I'll post later with some ideas of power usage during the race.
Powers to keep in mind (PH1 only, sorry):
For PC's (and "mirror" NPC's):
Ranger:
Hunter's Bear Trap (ran at 1)
Crucial Advice (ran util 2)
Unbalancing Parry and Yield Ground (ran util 2) - great for defence
Cheers!
Fighter:
Bull Rush FTW!
As Dragonborn - Dragon Breath - acid and fire. Just because he can't use it on other competitors, doesn't mean he can't destroy rope ladders/ and any such aid that is placed on track - and it's only a minor action!
Tide of Iron - to push off somebody trying to get on ladder and get on it himself
Get Over Here - to help out others across difficult ground that would require a check (see - LOTR dwarf tossing)
Warlord:
Wolf Pack Tactics - to let ally escape from troublesome NPC
Leaf on the Wind - like fighters Tide of Iron, but even better in narrow tunnels and trails
Knights Move - no comment needed

Shake it off and Inspiring War Cry - for those nasty traps
Hold the line - same. Also handy if they have to cross a very swift stream
Other notable (especially since NPC's can have them for multiclass!):
Wizard:
Icy terrain - not on characters but somewhere in front of them
Sleep, Expeditious Retreat, Feather Fall, Jump - no comments needed
Rogue:
Dazing strike, Positioning strike, trick strike, great leap, tumble
Bait and Switch - crucial in corridors/tunnels
Rituals to equip NPC's with:
- Water Walk is a "must" for all natives
- Hallucinatory Creature - one of the fastest participants, or maybe even already cast: a Beholder or something like that (don't be afraid of overkill) in front of tunnel or on top of cliff they have to climb. Don't "roleplay" it! Settle for some instructions, maybe even write them down - and keep to them.
- Hallucinatory Item - for organizers only. Cast inside of maze as wall. Arcana/dungeoneering check can unveil it as illusion.
- Linked Portal - for refs. Each ref will have two points to guard. They should be very cautious about it, but it's a possibility for PC's to have a massive shortcut
- Make whole - possessed by referees - to repair any crucial equipment on the trail. Of course note the time needed to finish it (competitors can help!).
- Phantom Steed - gamebreaking, especially at arcane check 40+, and even 30+. You might even have to ban it in race rules

- Passwall - used especially by race veterans who know where in tunnels it will create shortcuts.
Special equipment: caltrops (a LOT of them), climbing eq, various ropes, grappling hooks, oil flasks, tanglefoot bags, thunderstones...
* this baddie: [ame]http://www.youtube.com/watch?v=Krqbqh3bIww[/ame]