Help little Haku [C-mod trouble]

[Hakulyte]

Okay, little Haku recently got a game called Stepmania. After playing some pad-simfiles and passing them at beginner,
little Haku played with something cool called song option. Little Haku looked at Speed and saw that:



As you can see there is 2 special letter, the "X" and teh "C". While little Haku was looking at those awesome letter
there was something going wrong.

"I know what this "X" means! Really i do! But.. that C.. "

That mysterious "C" was seriously confusing the poor little Haku. So after trying a song in "C400" like ehm Sakura, little Haku realized that when the BPM was changing it was still easy to hit the arrows.

"Cool! I can hit that evil arrow that was coming super slow or gigadelicly fast huhu.."

*brb reading stickies*
...


So ehm there's teh question:

What do little Haku need to do so he/she/alien can play in C600? Because C600 is much more cooler than C400!

What i got atm is:

C:\Program Files\SM\Theme\metrics.ini

Then

find that place with c-mod and edit u_u..

emh ok cool but how? I'm a 5yr old little noob who don't know a lot about computerz and leetz stuff like that. I played only since Alpha SM version how the hell i'm supposed to know that.

Thanks for help.

- - - - - - - -

In other words, i just need to know what to do to change the c-mod.. and i'm tired.

Edit: I don't know how to speak (properly) in english.