I´m also not an specialist in this things but have an very good functional Hackintosh building completely myself including install opencore etc. with help from some good guys here for the first time. I´m scared to do an opencore update without help/instruction from the specialists here!
Also, keep your working system intact and use a bootable usb drive to check if your new config works. Only when you are certain it does, copy over the EFI file to your internal boot drive. Keep copies (I always rename my working EFI to something like 'EFI_063' so I can rename it from a terminal window if disaster strikes).