Dennis @ PerfectForms
Give your stages a number at the end of the stage name. For example customer1, managment2, production3, and closed4. Publish your form and map the old instances to the new version. Then when the report opens use a set filter behavior object. Set the field to meta-stage. Set the operator to less. Set the value to the name of your closed stage. The only instances that will show on the report will be those not in the closed stage.