Firmware update from Android used to take about 10 minutes, and still does on older phones and/or older versions of Android. CyanogenMod users are in a minority, I’m not sure if there are specific issues there. I can make 2 suggestions:
1. Can you ensure you have the latest version of the Mooshimeter app installed?
2. Do you have access to an iOS device? The firmware update runs much smoother from an iOS device (takes about 60 seconds), and it’s the same firmware that ends up on the Mooshimeter (if you’re interested in some of the BLE challenges on Android, check this blog post).
Please let me know if these don’t help and I can try to think of something else