To avoid possible confusion, Ave. de Independencia intersects Uria before the RENFE station. If you turn left on Independencia, it will lead you to the third of the line of cubist buildings. Then you can proceed as per instructions.
If you follow Uria all the way to the station, N-634 is called something else, not Independencia,
with Ave. de Santander the side street right in front of the station. Turn left there and you're fine.