After the intros, you'll be at the Dragon Nest title screen. There will be four options:
ホームページ - Home Page
ゲームスタート - Game Start
オプション - Option

And the last one is exit. Choose Game Start to begin.

You'll be at a screen with four different characters. Each character has different attacks, you can play the game with any of them, so just pick your favorite for now.

You have to choose from two options here, I don't remember the exact text, but you will have to pick
"キーボード＆マウス" because the second option is a gamepad option, but you HAVE to use a Hangame gamepad. In Japan, the company is huge enough to have their own gamepads. Though I might be able to do some coding for a PS3 controller app...We'll see, depending on the complexity of the pad.

Now you're in the Tutorial Dungeon. I'll just translate those onscreen messages.

Room 1: Basic Movement
Onscreen Image: W, A, S, D.
You can move your character with these basic controls. W moves forward, A strafes left, S strafes right, and D steps back.

Room 2: Mouse Movement
Onscreen Image: Mouse Left, Mouse Right.
You can move the camera with the mouse. This will also turn the character.

Room 3: Jumping
Onscreen Image: Space Bar.
The Spacebar is used to jump. You can't double jump, though. :<

Room 4: Basic Combat (may be out of order. Just follow the images.)
Onscreen Image: Left Mouse Button.
Click the left mouse button repeatedly to attack. Each character has different attacking styles, with a different number of hits. You'll do some hits in succession, then a more damaging finisher.

Onscreen Image: Right Mouse Button.
When an enemy is knocked down, target it and right click to do a finisher attack. This has cooldown (what)

Onscreen Image: AA, DD, SHIFT.
You can double tap A or D to dodge roll. Alternatively, Shift + A or Shift + D will initiate the roll. You aren't invincible, but you can cover a nice distance to get out of the way of attacks. This has a whopping SIX SECOND COOLDOWN. ARGH. Double tapping S will backstep, and double tapping and holding W will dash as long as you have the W key held down. These actions still have that six second cooldown.

Onscreen Image: AA, DD (You're fighting that bigger thing.)
When you're knocked down, double tap any directional key (W and S work, even though they're not shown) to DO A BARREL ROLL and get up. I don't think you're invincible, you're just fast.

Onscreen Image: I forgot. It's the one after the barrel rolling one.
Use the 1-0 number keys to use skills (argh). This works in a Tales of Vesperia style, you can attack normally and then chain that combo into an artechain. Think Hit, Hit, Hit, Skill (skillskillskillskill).

Tutorial Clear! Talk to the NPC and select the only option to proceed.

Now you're at a town. Talk to Lily (リリー) and select the クエスト option to start the next level. Selecting チュートリアル will redo the tutorial if for some reason you want to. Follow the quest arrow to the left dungeon. You can only do Normal difficulty, so click that and select the left option to enter the next stage.

Since you're going into a new dungeon, now's a good time to learn some other keys.
The I key opens the inventory, while the P key opens the character screen. With both of these open, you can change weapons. The R key revives yourself when you're dead, and it can also be used near a dead party member to give them a life. In this demo, you have infinite lives. In the real game, I think you're limited to three. Pressing E makes you automatically move forward, I don't recommend it. Pressing K brings up the skill menu, but you can't level up in this game. Speaking of EXP, notice the FTG bar? If you play a lot, this is bad for you, since each dungeon takes from this bar, and when you're out you can't play anymore. You can still PvP, though. There's three bars, Daily FTG which refills to 700/700 each day, and Weekly FTG which refills to 1000/1000 each week. The third one is NetCafe FTG...I think it's Korea exclusive.

Scoring:
You get score upon killing enemies, dealing finishing blows, breaking shields, doing successful arte chains (skillchains, comboes, whatever you want to call them), and breaking stuff. You also get points for using healing items, but only when they actually heal you. That doesn't mean you should be getting hit, getting hit makes you lose a sizable chunk of points. In the real game, score gives an EXP bonus. This is a demo, don't worry about it.

Stage 1: I don't remember the name, and my computer's pretty terrible, I don't want to wait for Loads and Loads of Loading to go translate this.

A pretty basic stage. Just go along, killing everything. I tried to take the game defensively, but unlike Kingdom Hearts, this game was designed to be more offensive. So get reckless. Really.

Stage 1 Boss:
Karaga (Level 10)
You're Level 16 in this demo, so this is an incredibly easy fight, unless you somehow get infinited. That does happen if you have a slow computer.
Watch out for the red magic spots that appear on the ground. If you're there for too long, the boss will hit you with lightning for minor damage. Again, since you're overlevelled, just get reckless and you'll win pretty quickly.

After the boss battle, there's a cutscene where Dumbledore dies. I mean what...

Talk to the NPC to proceed, always pick the top option if there's a choice.

You're back in town, that NPC should have given you a quest. I'm not so sure, talk to Lily again just to be safe. Top option. Now head to the right dungeon, select Normal, left option.

Stage 2
This stage is a lot harder. And by a lot I mean not that much harder, then DRAMATICALLY harder. Sometimes you have to activate crystal switches to proceed. To do so, get close and left click. It's an easy stage at first, but soon you'll reach...

Midboss: Minotaur x 3
These guys won't appear until you break the large diamonds, make sure you only summon one at a time. My first death was dealing with 3 at a time with the warrior. To make sure you don't accidentally summon more than one, summon one then lure it back to the pathway. After it's defeated, walk down the path it came from and hit the switch. Deal with the rest the same way. Then...

Boss: GIANT Minotaur, level Something Higher Than Yours
This boss is difficult. It has several attacks, I'll explain them below.

Axe Swing
This guy's axe is pretty big. For the first half of the battle, stay as close to it as possible. When it raises its axe, dodge roll to the side and get behind it.

Charge
When the boss rears its head and looks like it's about to charge, dodge roll to the side and get behind it. But if you're not as close as possible, the roll won't make it. If you're a bit further, you'll need two dodge rolls. This wouldn't be as tough if rolling didn't have that cooldown...

About halfway into the battle, the boss will enter Desperation Mode. His attacks get faster, and he can use...

Overlimit: Blue Axe Swing Thing.
"Get Behind Him To Not Die." The attack has the same callout as the normal axe swing, and the method to dodge it is the same, so just make sure you're behind him.

After the boss is defeated, you'll see another cutscene and you'll be placed in an area. Talk to the NPC...to end the demo. Left option is to go to the homepage (IP Block! Oh noes!), right option restarts the demo.