Is it possible to open a map created in unreal engine 4 in unreal editor so I can add Unreal Tournament items?

I have blocked out a map in unreal engine, but I wanted to make it for Unreal Tournament (CTF). I know now I should have started in unreal editor but when I began and was using tutorials they were mostly in unreal engine. Can I open this map in unreal editor to add the Unreal Tournament items (pickups, weaps etc)? I’ve searched the net for answers but can’t find any. Please advise, I really hope I don’t have to start from scratch in Unreal Editor.