iD-ToX

How can I convert a patch to another firmware version? I wanna convert patches from XEFC1 version to XCEJ4 version. I know it's possible, but can anyone help me? Another thing I would like to ask is... why when I try to save a firmware with ResMan 5.4 it gives an error in the midle of the save process and with ResMan 4.1 it goes alright? Thank you people and I hope I finally find this answers!