There doesn't appear to be a way to duplicate a piece that has been imported and rotated. You currently have to import the stl a second time and then reapply any scaling or rotation.
I'd also like an option to lay out the items on the platter differently. Currently it lays them out in a row along the Y axis. I'd prefer them to be in a row along the X axis. A final option would be to take up the least space in the centre of the build plate. So if I had 9 2cm cubes, instead of them running from one side of the build plate to the other, I'd like three rows of three placed in the centre. I try and avoid printing near the edges of the build platter on my printer for various reasons.
One final request, unrelated to the above. The machine control panel with jog controls and all has a windowing mode where it is completely independent of the main layout window. This means if you alt-tab to the app, the control panel doesn't come to the front with the main app. This is the sort of thing I'd prefer to be configurable and I'd configure it to always come to the front with the main window.