There is one thing I am really not happy with but just could not figure out how to do better and still get this in tonight. I am using a timer event to fire running the dirty objects and test their Constraints because I could not find an Event in any of the Eco services that fired everytime any attribute or association changes on any object. I kind of concluded that there may have never been a request by anyone to get that - and I didn't want to take the time to add my own object by object watcher. Maybe I just missed it and someone can tell me about a way to do this. I guess I also assume that a stack of subscriptions would do the trick but again that is more than I wanted to do for this sample.
Also, the Command wrapper I have is all WPF specific so I will have to make a WPF sample to show how that works.
I didn't add many comments and there may be a need to use Weak References that I have not explored yet - the way I did it I htink they might not be necessary.(?)
Enjoy...