Found a similar problem: the demos work on 4.4.3 (Nexus9) and 4.3.3 (Samsung GT19300) but not on 4.4.2 (Doogee DG800). This section of the ListBeaconsActivity beaconManager.setRangingListener(new BeaconManager.RangingListener() {
@Override
public void onBeaconsDiscovered(Region region, final List beacons)
Log.e(TAG,"Ranged Beacons " + beacons); may hold some clues.
The class beacons is populated correctly in 4.4.3 & 4.3.3 but contains null values in 4.4.2.(Therefore: beacons.size = 0)