OK, in an attempt to defibrillate my GPS: Ran a new Nandroid backup, cleared all caches, flashed Sprint Lovers, booted to SL, ran MSL Reader, entered code, auto rebooted after 10 seconds, waited until booted into SL again (my wife called me)
, then I rebooted into recovery, wiped caches again, nandroid back to RC9...
Voila! My GPS has been resurrected!
Looks like the Sprint Lovers ROM is what did the trick. Thanks! Now to attempt RC10 (I just don't know when to quit)...