How Do I Tweak Someone Else's ROM

[psykotik312]

Guys I have searched until my eyes are blurry and I can't find an answer. My problem is that I'm about to start cooking my first kitchen and I want to tweak NFSfan's v12 just a little to better suite my phone uses, at least for my first few tries. I'm using BuildOS's kitchen. Is there any way to load that ROM and let BuildOS take it apart and let me tweak it?

I'm sure its a simple copy and past but I don't know which file to c&p. Thanks for your time and please feel free to flame the n00b as long as you point me in the right direction!

[puff]

check out rstoyguy's tutorial How to Customize a Custom Rom: Adding/Removing Programs

Note: if NFSFAN puts some kind of protection on the ROM then you might not be able to decompile it properly with prepit