It seems to work with the 17134.1
My only wondering after creating the RS4 folders is I don't get the "INFO : Mounting -----> START  = ISO Mode [xxx.iso]"
but a "INFO : Mounting -----> START  = Folder Mode"
I create the .iso with the UUP download and conversion to .iso with .Wim

Is it due to my pre-RS4 .iso or to 1.9.15?

THanks for clarifying

I forget to mention that it was OK with .iso created with 17133.1