I tried to show SH5 to my uncle up at the lake this week and had problems. But I did finally get it connected and was able to who it to him. But I was staying next door, at my aunt's cottage, and she does not have wifi. So, I found myself leaning out the window, or walking around they yard, just to try and get on his wifi for 2 seconds to connect so I could play. That sucks.
At least Steam has an Offline mode that is supposed to let you play when not connected. It worked at first, but then it started asking if I really wanted to start in Offline Mode, and when I clicked Yes, it said it couldn't connect to the server and ended. WTF!!