No cell service in Moto E after restoring Stock ROM backup from CWM.
I've faced a similar issue when I flashed CM12 into my Moto E XT1022 and reverted back to stock.

The solution was to boot into fastboot mode, erase modemst1 and modemst2 and flash the NON-HLOS.bin of KK ROM.

You'll need the stock ROM files in order to do this. NOT A ROM BACKUP.

The commands to use:

fastboot erase modemst1
fastboot erase modemst2
fastboot flash modem NON-HLOS.bin
fastboot reboot


After the reboot, it might take some 5 minutes to get a signal. IF you still don't get a signal, try this:

1) Open the dialpad and type: *#*#4636#*#*

2) Head over to Phone Information and scroll down to Set preferred network type.

3) Try changing this value after waiting for a few minutes.