I have a finished model that has been saved as a model tool in a custom toolbox. I add the toolbox to ArcToolbox, double click, set the parameters, and run just like any other tool. I have the model setup to add certain results to the map display. However, when running as a model tool and not in edit mode, the results will not add to the display. Is this a workspace environment issue?
Try making the output a parameter and then it should add it to the display when you run the tool from the toolbox.
The output datasets (green objects) have to be set as a parameter and uniquely renamed. In addition, the workspace in the model must match the workspace in the map document. In other words, same path to the same geodatabase. This will allow outputs to be generated in the ArcMap TOC upon completion of the model tool.