Hello Roby,
Bill of Materials as Reports are based on Crystal Reports (.rpt files in C:\Program Files (x86)\Bentley\Plant V8i\Reports). In order to create custom BOM existing report should be modified or a new one should be created. AutoPlant SS4 was upgraded to support Crystal Report Engine 11.5.
In case existing reports have required information in it is possible to add or remove columns from BOM using Options in Bill Of Material dialog.
Below is link to (How Do I Use Crystal Reports To Add Fields To My Report [TN]) Tech Note.
communities.bentley.com/.../how-do-i-use-crystal-reports-to-add-fields-to-my-report-tn.aspx
This Tech Note covers field addition to existing rpt and column selection in Piping BOM.
I hope this will help.
Regards,
Artiom