How To Create Single IsoSheet for Multiple Pipelines

Set OPM_ALLOW_MULTI_PIPELINE_ISOSHEET=1 in Modeler.cfg.

Open the Pipeline Manager from the Piping taskbar.
Select the pipeline in the grid to load into the IsoSheet Manager.
Select the IsoSheet Manager icon .
In the IsoSheet Manager, click the Pipeline list icon and pick the Select All option.
The components from all of the pipelines display in the component grid at the bottom of the interface.
Select all of the components from the list to include on the IsoSheet.
Click the Create a new Isosheet icon.
This will run the connectivity checker on the current components selected and if no disconnects are found, it would create a new Isosheet associated to both the pipelines. Otherwise it will give an error.
Define the properties for the iso sheet in the ensuing properties dialog.

Note: A Design State must be defined for the iso sheet before it can be run in the Iso Manager.
When finished defining the properties, click Save to create the Isosheet.
This newly created Isosheet would be listed in Isosheet Manager's Isosheet list, where we can perform the standard operations on it for example edit, delete, remove components etc.