The proper files are loaded (based on the date) whenever you open a campaign. So, to update the files in your campaign, just go into CM and open the campaign. You'll know it's happening because the first time you do it, MANY files are copied. So, when you start a campaign, before you fly a mission, you have to open it in CM. You don't have to worry about it after the file copying is done-- just press on. After each mission, you could go back to CM and open the campaign again (to update the files) or, if CM is already running, you can click "update" and it will take care of it.