Not that I can think of off the top of my head.  Sometimes nested resources don't work right without overridding some of the resource controller helper methods, but that model isn't nested so not sure.  Adding spree. before edit_object is the first thing I would try but not sure it will make a difference.  Although it probably will if your spree store is not mounted at root.  Where did you mount the spree engine in your routes.rb?