Copy/paste works, even between different projects if you are careful to copy in the globals first and then the events that reference them. (Not sure about moving both together.)
EDIT: You also need to have created all of the other objects/assets referenced in the events or you'll get errors telling you you cannot paste because something is missing. This includes instance variables created on objects.
BTW, if you don't find Paste in the context menu when you right click on an event sheet, don't forget Paste on the toolbar.