For all those not getting your computer to recognize the phone through the COM PORT, turn off the phone while it is plugged into USB and run the whole process from there. That worked for me thanks to a tip over at XDA. I am running the hybrid 61677 and loving it.
Got my MSL and zeroed it out with no problem, first try.
However...
I tried multiple times several days back to get the PRL to stick, but it wouldn't write from CDMA WS or QPST. Phone would reboot with the same 61007 PRL.
I tried with the phone fully booted, and in recovery mode, but it wouldn't write the PRL either way.
So, after reading this, I tried to write the PRL while the phone was booting up (my desktop computer couldn't see it while fully turned off,) and QPST wrote the PRL cleanly; phone rebooted before it was fully booted up; and the new PRL showed up on the phone after that.
YAY!
Thanks for all the info, and the hybrid PRL.