When you create and save a project defined report, the saved reports will also show in different room windows in dRofus panels so they can be used directly for e.g. an open room data sheetfrom the open rooms panel. If you open a RDS Room Data for a room and press select "Print" you can see that the saved reports are added to the list:
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Where the saved reports are shown depends on what type of report is being saved. E.g. all Room Data Sheet reports will show in the room RDSRoom Panel. All Template Room Data Sheet reports will show in the template RDSTemplates Module. Saved Item reports will show in Items in room etc.
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