Currently for Supports, symbols are defined based on support classes. In some project, it is required to use only one symbol for all support classes. Below article will explain the case by modifying Isometric Component custom attribute and removing the class name entries from it. See below steps.
http://communities.bentley.com/products/plant/design___engineering/w/plant_design_and_engineering__wiki/13393.settingsattributes-openplant-isometrics-manager
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