In OpenPlant Modeler there is a possibility to place Detail Callouts, but after placing one, saved views or sheet models cant be created.Below you will find steps how to fix this issue and place Detail Callout in your model.
http://communities.bentley.com/products/plant/design___engineering/w/plant_design_and_engineering__wiki/30033.how-to-place-detailing-symbols-in-openplant-modeler
http://communities.bentley.com/products/plant/design___engineering/w/plant_design_and_engineering__wiki/30027.how-to-get-detailing-symbols-like-section-callouts-updated-with-drawing-information
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