The crux of the route is definitely to find a bodyposition that allows you to not only reach but also make use of the undercling for the right hand. We had fun experimenting and trying different things!
Rain sucks, but broken holds suck even more. Remember, never climb on wet rock in Fontainebleau.
The sandstone becomes brittle, and pulling on it will ruin classic problems. Drying it doesn't help, because it's still wet and weak inside.
All you can do is wait for better conditions.