@eilonwy42,
I guess so, that's what I did. I'm not an expert or anything, just wanted to figure this one out.
Bfifty, I don't understand the elimination process so I don't know what to say about it except for our answers don't match, but I'm not 100% sure about mine.
Edit: I don't know why our numbers are different. I got the diamond and 4 ending passageways with only one connection.