uh... I don't think so
I don't know where you got the raw, but you can check it at the official raw site
go to the
chapter list
you can see the first page of each part there, then you can divide accordingly
if you got the raw from the actual volume, the chapters are clearly divided by a blank title page
your translation is pretty good
part where you said you couldn't translate that well, I think you just make it better than the original