Apparent overlap issues for Exports in ToD stacked column graphs

[aleith]

I may be misunderstanding how data element stacking is supposed to work for imports and exports (I know it does my head in sometimes looking at the graphs with many of the technologies removed from the displayed data and the data dropping below the horizontal axis!), but seems to me that Export data should not overlap other technologies or imports and yet it seems to be in this graph for SA with just batteries and imports/exports selected for view.

removing imports, still doing it:

removing exports from the selection, now it's disappeared. t.f. seems to be an issue with exports not drawing properly.