Index: trunk/scripts/SyncEditorLayerIndex.groovy
===================================================================
--- trunk/scripts/SyncEditorLayerIndex.groovy	(revision 13533)
+++ trunk/scripts/SyncEditorLayerIndex.groovy	(revision 13536)
@@ -272,6 +272,8 @@
         stream.write "<imagery xmlns=\"http://josm.openstreetmap.de/maps-1.0\">\n"
         for (def e : entries) {
-            def best = "eli-best".equals(getQuality(e))
-            stream.write "    <entry"+(best ? " eli-best=\"true\"" : "" )+">\n"
+            stream.write("    <entry"
+                + ("eli-best".equals(getQuality(e)) ? " eli-best=\"true\"" : "" )
+                + (getOverlay(e) ? " overlay=\"true\"" : "" )
+                + ">\n")
             stream.write "        <name>${cdata(getName(e), true)}</name>\n"
             stream.write "        <id>${getId(e)}</id>\n"
@@ -608,4 +610,13 @@
                 }
             }
+            et = getOverlay(e)
+            jt = getOverlay(j)
+            if (!et.equals(jt)) {
+                if (!jt) {
+                    myprintln "! Missing JOSM overlay flag: ${getDescription(j)}"
+                } else if (!options.nomissingeli) {
+                    myprintln "+ Missing ELI overlay flag: ${getDescription(j)}"
+                }
+            }
         }
         myprintln "*** Mismatching shapes: ***"
@@ -936,4 +947,9 @@
             && e.get("properties").getBoolean("best")) ? "eli-best" : null
     }
+    static Boolean getOverlay(Object e) {
+        if (e instanceof ImageryInfo) return e.isOverlay()
+        return (e.get("properties").containsKey("overlay")
+            && e.get("properties").getBoolean("overlay"))
+    }
     static String getIcon(Object e) {
         if (e instanceof ImageryInfo) return e.getIcon()