Hi, Max, I try to help you, so we made Rio di Valgrande from Ponte di Velina to Ponte Casletto, there are 2 ways to put in, the one along the river is a bad trail that can be very dangerous in wet weather, the other way is take the trail before Casletto that lead to Alpe Bettina and then to Velina, it' an easy way, we spent the night at Velina, it is possible to go up and put in the river at Alpe Orfalecchio, where is possible to spent the night, more over there is the himalaian portage of The Arca, I don,t suggest to you.
The run is a IV/V degree that needs not much water, now the level is OK.
By Alberto.