Sounds like you don't own the app so all I can suggest is you ask whoever it was if they will give it to you.
I borrowed photo dvd slideshow program named Photo DVD Maker about two years ago. The version I always use is 8.20 but recently it promoted me to upgrade, so I upgrade to the latest 8.51 version. In fact, I don't like this version, because I am not familiar with the buttons position and I don't want to spend time on finding these options. So I'd like to go back to my old version, BUT I can't find it on my computer. , so now, how can I get back my 8.20 version of Photo DVD Maker?