Applicability of hacks

So why can't people use a GCBR hack in GCNA or other region?
Is that becuz of the difference in client version?
Suppose the files should be the same(except some .stg)

This is because the updates are different,
In GCBR hack just came out because of Wanderer release,
And it uses Wanderer's files to actually hack the game.
GCNA doesn't even have the Rin/Lin jobs yet.
That's why you can't use hacks on other regions with a hack from one.
eg : GCPH hack on GCLA,Def wont work.

Nop. /\
A trainer is a program that writes to remote process memory.
main.exe from GCBR doesn't have the same memory addresses as GCPH, KR, etc