Is it posted as a work in progress in the forge discussion forum, or is it in the Maps database?
If it's in forge discussion, just reply to the thread, showing the changes that have been made. If it's in the Maps database, anyone who's following the map will be notified of the update. You could also reply to the thread with a list of the changes you've made to the map.
No, please don't do that. Just reply to the map thread, leaving a list of the changes made in your update. While doing an 'Update' to your map thread will not bump it to the top of the Maps database, replying to it WILL bump it up so people can see the changes.
Comments on Profile Post by a ninja samuri