Frank
I also use the 5mm/50laps settings which about got rid of the weather auto pits. However you're not entirely safe from those advanced settings. Last race after rain started I had to select pit manually, as intended, but 2 or 3 times during that lap I had to switch my selection back to wets because the game kept switching them (back) to the inters from advanced settings. At least finally my selection stuck before the pit stop happened, two other managers had less luck there though.
That's what I'm talking about. Depending on luck and good internet connection that would allow you to switch it back to wets or cancel the pit-stop several times is not something you expect while running the rainy race :\