I'll only add some info about this case when you receive an error message and V_klay asks you if it should make repair patch. When you apply graphical patches you don't need to worry about those errors because there are many patch authors and they may already have different from the original data in the phone and they will not interfere with the firmware later. HOWEVER, in the case of conventional patches you need to be careful when you get that dilogue. I advise you not to apply patches which collide with anything in the phone because they may later cause problems or even unable the phone to be turned on. That's why G_spot has written about making a register of all patches applied - that is crucial for keeping your phone firmware tidy
