We were in Navarrenx last year, if you are stopping at camping Beau Rivage you will not be dissapointed, its a cracking little site.Navarrenx is a lovely town.
As for stop overs we stopped at Le Chateau de Leychoisier near Limoges on the way down,and camping du futur near Tours on the way back up.
We stayed near thee last June and stopped at the municipal site by the lake at Bessines sur Gartempe near Limoges, 1 day to BSG from Calais and about 6 hours to the Pyrenees from there.