GATT connection timeout?

That all looks fine... I just tried it between two Pucks using their UUIDs:

var DevName="Puck.js b0ca";
var serviceUUID="6e400001-b5a3-f393-e0a9-e50­e24dcca9e";
var characteristicUUID="6e400002-b5a3-f393-e­0a9-e50e24dcca9e";
var MessageToSend="LED1.set()\n";

function SendCommandToActuator() {
  NRF.requestDevice({ filters: [{ name: DevName }] }).then(function(device) {
    return device.gatt.connect();
  }).then(function(g) {
    gatt = g;
    console.log(gatt);
    return gatt.getPrimaryService(serviceUUID);
  }).then(function(service) {
    return service.getCharacteristic(characteristic­UUID);
  }).then(function(characteristic) {
    return characteristic.writeValue(MessageToSend)­;
  }).then(function() {
    gatt.disconnect();
    console.log("Done!");
  });
}

... and it works fine, even with the Bonding.

Do you know where the error occurs? At getPrimaryService? I guess you could try delaying the call to getPrimaryService and seeing if that helps?

Also perhaps you could try NRF.on('disconnect', function(reason) { print("Disconnected",reason) });

It might help to understand why the connection broke down.

Otherwise I'm not sure what to suggest - if somehow I can get one of the magic devices here then I might be able to figure out why it's not working.

Otherwise if you have an nRF51DK then you can use Nordic's tools to sniff all the BLE packets - which might help to figure out why things aren't working.