Index: applications/editors/josm/plugins/imageryadjust/src/imageryadjust/ImageryAdjustMapMode.java
===================================================================
--- applications/editors/josm/plugins/imageryadjust/src/imageryadjust/ImageryAdjustMapMode.java	(revision 27494)
+++ applications/editors/josm/plugins/imageryadjust/src/imageryadjust/ImageryAdjustMapMode.java	(revision 27540)
@@ -69,5 +69,5 @@
             adjustingLayer.setVisible(true);
         }
-        Main.map.mapView.addMouseListener(this);
+       Main.map.mapView.addMouseListener(this);
         Main.map.mapView.addMouseMotionListener(this);
     }
@@ -146,4 +146,6 @@
      */
     protected Layer askAdjustLayer(List<? extends Layer> adjustableLayers) {
+        if (adjustableLayers.size()==0) return null;
+        if (adjustableLayers.size()==1) return adjustableLayers.get(0);
         JComboBox layerList = new JComboBox();
         layerList.setRenderer(new LayerListCellRenderer());