Fumanal is on your map.
Congratulations.
From
L'Ainsa take the road for Campo. Turn right
after 13 km where
Tierrantona is signposted.
Leave the main road where
Muro de Roda is indicated (right turn to the village school).
Follow the small road past the school-yard and drop the car where a small river crosses your path. You could continue by car,
but it really is such a nice walk you wouldn't want to miss it.
Walk up-hill until you find the first GR-1 markings. At that
point leave the dirt road for a smaller track (you are on the GR
towards Humo de Muro) which brings you to the mill after few steps more.
Pictures: 03.xi.2000, viii.2001, 03.x.2018