A: 

You are passing a NSDictonary to rowsArray as your JSON data seems to be a dictionary nested within a dictionary. So I would assume that is causing rowsArray to be empty and cause the crash when you try and add it to your mutable arrray.

Robert Redmond
I've used this before, is this statement incorrect for a nested array? rowsArray = [dict objectForKey:@"member"];
Michael Robinson
The JSON data looks like nested dictionary. "Member" the first level and the the other level looks like key-values ie: "user id", "18" etc.So it would be NSDictionary *rowsDict = [dict objectForKey:@"member"];The easiest thing would be to get rid of the "member" level by manually editing it out of your data and then you are working with just the one dictionary.
Robert Redmond