Assuming the alternator is good, then it requires a working regulator which is usually screwed to the back. A good earth to engine, the engine earth itself to chassis to be good and the live wire from alternator to battery to be good.

The only other part of the circuit is the exciter lamp which in your case appears to be working.

However, on your car, you may also have the Ford active charge technology which means the ECU has control of the charging circuit, that requires further investigation if the usual causes of no charge are ruled out.