Hi Val,
 I’m sorry, I don’t know a lot about the château at Cornusson. I’ve had a quick look on the Internet, hoping there might be a Wikipedia article about it but it’s only mentioned in relation to other things.
As far as I know, it was probably built in the late 15th century, added to and altered in the 16thand 17th centuries. It’s also connected with the De La Valette family of Parisot, one of whom (Jean) was Grand Master of the order of Hospitaliers de Saint-Jean and drove the Turks from Malta in 1565. He is described as ‘Seigneur de Cornusson’ but was actually born at the Château de Labro, next to the Seye not far from Parisot and now virtually in ruins.
 The château de Cornusson is privately owned and not open to the public. It’s a listed historic monument.
 That’s about all I know. I can only suggest scouting about on the Internet to see what can be pieced together. There is an old ‘History of Parisot’ (early 20th century), of which a rare copy is held at the Parisot Library and which might say more. But… it’s in French, has no index and can only be consulted in situ.   
 Hope this helps a bit, anyway.
Vanessa x
Vanessa x
Val says I emailed Vanessa who by writing a blog "Life on the lune" has become  a local expert . Many thanks Vanessa, but if anyone else knows more please tell us.
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