The EGR valve sticking is a common problem. So much so that many members recommend replacing it every other oil change. You can do it yourself even if you don't change your own oil. Do a search & you should find several threads on the subject.

The MAS situation is less common but several others have experienced similar problems (including myself). Mine would lose power on hills if I let the tank get below half. Fortunately for me, it only required a good cleaning rather than a replacement. I'd recommend you put in a bottle of fuel injector cleaner at your next fill up & replace your air filter. If the MAS was clogged, the airfilter is probably dirty too.

Hopefully this will be the end of your woes & Dragon will stay healthy. Let us know if you get any more symptoms.