5. The computer program product in accordance with claim 1 , wherein the computer-executable instructions are further structured such that the computing system further performs the following: an act of displaying a hierarchical visualization of multiple model elements in the hierarchical structure of model elements in a viewer, the hierarchical visualization including a visualization for each of the multiple model elements.
5. The computer program product in accordance with claim 1 , wherein the computer-executable instructions are further structured such that the computing system further performs the following: an act of displaying a hierarchical visualization of multiple model elements in the hierarchical structure of model elements in a viewer, the hierarchical visualization including a visualization for each of the multiple model elements. 10. The computer program product in accordance with claim 5 , wherein the model element of the first model element type is a placeholder model element that is not executable.