How to run old tests for the new version of the application under test?

if you hav changed the name of exe for new exe you can not run old test with same name mapping.
eg App.exe ==> to App_new.exe to tacle that keep two exe's in different folders with same name and
and you can hav 2 or more test tested apps in a project. So can map two versions to different locations in tested apps.

But still your object properties (mapped) have being changed eg ojbect WndCaption "loggon" ==> "User_loggon" then you hav to change mapping properties it self
to avoid that you can use conditional maping. eg you know WndCaption allways will have something like "loggon"
can use *log* insted of "loggon"

following links have more.....

http://support.smartbear.com/viewarticle/55443/

http://support.smartbear.com/viewarticle/55608/?utm_source=site-search&utm_medium=search-results&utm_campaign=site-search-c&utm_term=conditional+mapping&_ga=1.137575737.809719160.1405381514