Before you can play around with the entities of q4run you have to make some settings first.
I always create a completely new folder for editing purposes only, so I don't get any problems on servers later because of a different version of the map or because of different pk4 files. Extract q4run again into your quake4 folder and name it something like q4runeditor. Now you also have to edit your shortcut to the editor:
Run the application and look if you have a target_timerstart in your entitieslist. It should appear because the editor also loaded the q4run definition files besides the normal quake4 files. For the last step go to edit -> preferences and link the map path to the q4runeditor folder.