Hi. You've probably found some sort of solution by now, but I don't think you'd be able to automatically separate out the items by layout tab as they effectively all exist together in the 'Global' tab. The 'Global' tab in ESTmep is effectively the 'Model' tab from AutoCAD, so the layout tabs are just views of this.
There is a 'drawing name' property for items, so you could select all items on a layout manually then assign a certain drawing name/number, and create a report that separates the items out by this.