mtkflash r /m orig.bin is the command i use. /m is for multiple banks in the bios.
i hope i don't sound patronising, but u do know that the R command is only to read the bios?
once this is done, hex edit the orig.bin to get ur drive key and copy it into the hacked firmware bin image (or use x360sam - its loads easier) and save it as for example hacked.bin
now tap in "mtkflash w /m /t hacked.bin"
the /t switch in the command should give u a moderately accurate time til completion.
hope this helps.