So, I have this assembly:

But then time goes by, I modified some part (only God knows which one) and next time I open it, it looks like this:

However, if I open it in the large assembly mode I can still see it perfectly as it once was. 

This is somewhat trivial to rebuild but I have two questions: 1) Is there anyway to identify what has been changed ? I see that only a couple of constraints have changed so that gives me an idea but maybe there´s a better way and 2) Can I generate a drawing from this assembly somehow ("save as" is non existent, and "generate drawing" also).