What about user support ? Can you write and get an answer from the author in a reasonable amount of time ?
By now there is a very active Google Group.Wrote a question yesterday and had an answer within 10 Minutes. Very friendly vibe, mostly Rubyists dabbling into Xcode, but also some very nitty gritty in depth topics.
Also the BubbleWrap repo (https://github.com/mattetti/BubbleWrap) is chugging along nicely, cool for a young project... So, yes: you can get help.