The most memorable "all's well that ends well" experience I can think of was during my days of college theater. We had one production that seemed like it was doomed from the start. We had to replace three lead actors for different reasons during rehearsals, then the lead actress suffered a heart attack. The technical director came up with a set design that was extremely complicated, and we never could get the changes right. Ticket sales were low, and the school wasn't happy with the adult nature of the play.
Despite all of these setbacks, we managed to sell out the seats for all three performances, and we got really great reviews from the audience. All that really mattered for us was putting on a good performance, even if everything else was falling apart around us.