Property promotion is done when the XML form is saved or submitted to the server. So, let's say you have 5 properties promoted in your form template. Now, you save a form to SharePoint - those 5 properties are extracted and promoted. Then, you go back to the form template and add a 6th promoted property. Of course, since the form you previously submitted hasn't been re-touched, the 6th property doesn't appear. You need to open and re-save the form. Or copy it down and re-upload it. Then the 6th property will show up. We have a bulk upload tool that we sell for like $10 which allows you to download hundreds of forms and upload them all at once. But, for a handful of files, just manually open and resave.
Patrick Halstead
Project Manager at Qdabra