I have never done a WoR, but that's just because I live in Europe and it's been difficult to work one into my schedule. I would have loved to attend one.
I have done all the other options, and where books are concerned I would say the top two things to read are Mike's book and Mik Hunter's Abused Boys.
Apart from therapy, what has helped me the most has been regaining my ability and willingness to talk about things - even when I have been totally lost, just talking has been great...at least I could see I wasn't alone. That's the most important aspect of a site like this: you know lots of guys reading your posts will know exactly what you're talking about.
Signs of improvement: that's a tough one. I would suggest bearing in mind two points. The first is that an abused boy usually carries his burden for years before he faces it, so it's not something that's going to be solved in a short span of time. If you look for indications that you are doing better in the short term you probably won't find much. I always saw signs in my own recovery when I compared myself to the same time a year ago, or better, two years ago.
The other point is that "signs" of progress can be deceiving. Sometimes we are doing important and productive work, but we don't recognize it because we are hurting so bad. Progress can hurt, bro! And on other occasions it may seem like we are getting nowhere for a LONG time, and then suddenly the log-jam seems to break up. What we need to bear in mind at those moments is that all that work that seemed to be producing nothing was in fact preparing the way for the big progress we think we achieved in a second.
Nobody living can ever stop me
As I go walking my freedom highway.
Nobody living can make me turn back:
This land was made for you and me. (Woody Guthrie)