Both visually and technically.
Potentially, this could also be done with the range selection tool. Say you already have Spectralayers applied to a region. Using range selection on the part of the audio you want to alter will also select the same spot in ARA2 Spectralayers.
Indeed something to explore,as we want to push the Cubase/Nuendo/SpectraLayers interactions further in the future. We have to be careful with that though, as it should not become an undesired side effect (for instance if you have a complex selection in SL and you suddenly lose it because you changed the selected time range in the DAW).
Selections are part of the Photoshop undo history, maybe that could be possible within spectralayers?