If you make changes to a resource file and then click OK to close the resource editor without having clicked the Save tool, the changes are saved in memory, the editor is closed and you return to the list of resource files. When you click Close in the list of resource files, a confirmation box is displayed asking you if you really want to save the modified resource file. If you click Yes, the changes are saved in the resource file itself. If you click No, the changes are kept in memory until you close the PowerDesigner session.
The next time you open any model that uses the customized resource file, the model will take modifications into account. However, if you have previously modified the same options directly in the model, the values in the resource file do not change these options.