Thank you. I was able to successfully edit gps.conf in vi. Agps now seems to work for me (i.e., I can generally get a fix in seconds now, compared to several minutes with gps only), with a change to an ntp.org NTP server. Flashing the radio was unnecessary. In the Settings>Location menu, clicking "High-accuracy positioning" and "Device-only mode" seems to work the best for me, though I did not test that rigorously (so that may not be a real finding). I am on the hardware adaptation associated with the CM12 2.0.1.11 image, OTA'd to 2.0.5.6...