The details of the challenge are below;
-Expert Difficulty (no changing it)
Then...
-Enter these into the console"
player.forceav healrate 0 (this makes health act like how it does in Oblivion (and Morrowind? Don't remember. No more regeneration)
player.forceav magickarate 2
player.forceav staminarate 4
player.forceav health 50
player.forceav magicka 80
player.forceav stamina 50
-No fast travel, but you may use the caravan service located out of major towns
-No "Waiting", but you may sleep.
-You cannot buy materials for crafting, if you do decide to craft- you must gather everything yourself. This also means you cannot buy soul gems.
-When you die. You're dead.
But yes, this makes it rather fun and challenging. Makes dragon fights way harder, too...feel more like dragon fights. Of course, I know this won't be suited for everyone...cause everyone likes to play different

And if you want a couple immersion/roleplay rules...which will end up coming as a mod for PC, but till then...
1. Must eat and drink in the morning, afternoon and evening. Take food and drink(s) with you into caves/dungeons! This makes food quite a bit more useful
2. 6 hours of sleep a day, one day a week can be missed. This won't count in caves/dungeons, but your character will be very tired after a dungeon experience and will need his sleep.