Help, Please explain the different parts

[Guest om1]

I am trying to understand the different parts of the rom update.

I downloaded an update for an smt5600/c500 etc..

I get the package to update the rom.

there are 4 parts of the package that i extracted:

enterbootloader, nk.nbf, rom update, and ruuget info

the .nbf file contains: SPL, Splashscreen, GSM, OS, and IPL

Is the .nbf file the actual rom itself?

Which part is the bootloader? How would I take the bootloader and put that on my phone? I have the IU test loader now, and want to go back to an older version from magneto to ontario rom.

I guess I am just trying to understand which part does what and what the nbftools can do to enable me to restore a version of wm2003se from wm5.

THank you for you time and patience with me, still so new at this, but learning everyday.