Main firmware file?
You need the K770_R8BE001_MAIN_GENERIC_VI_RED53.mbn
If the firmware in your phone isn't R8BE001, then before unlocking you need to flash the the K770_R8BE001_MAIN_GENERIC_VI_RED53.mbn with jdflasher.
I don't know how to make rest files
Copy the MAIN firmware to {Far manager folder}\Plugins\jdflasher\rest\ folder. Now drag and drop the MAIN onto mkrest2.exe icon.
and qa files with setool
Copy the MAIN firmware to {SETool2 Lite v1.11 folder}\qamaker\ folder. Drag and drop the MAIN onto qamaker.exe icon