When adding a new modification to your project, you assign a unique name and a project description, if required. You further specify any existing modifications your new modification depends on and the ones it cannot be combined with. Visum then loads the base version and all its modifications. Below the toolbar, a message is displayed informing you that the modification is being edited and all changes are saved as a definition of the modification.
Now you can use all editing functions to change the model. Data processing, however, is disabled in the Project view. After making all your changes, on the Information bar, click the Finish button to finalize the definition. Visum calculates the differences between the current model and the base model. These differences are saved as content of the new modification.
Of course you can add modifications during any stage of your project. You can also change modifications later on. You can further have the content of modifications displayed any time.
