diff --git a/extensions/wikidata/module/langs/translation-en.json b/extensions/wikidata/module/langs/translation-en.json
index a8d3b5cd5..89e3f7dc5 100644
--- a/extensions/wikidata/module/langs/translation-en.json
+++ b/extensions/wikidata/module/langs/translation-en.json
@@ -27,7 +27,7 @@
                 "label": "Label",
                 "description": "Description",
                 "alias": "Alias",
-                "item-or-reconciled-column": "item or reconciled column",
+                "item-or-reconciled-column": "type item or drag reconciled column here",
                 "amount": "amount",
                 "unit": "unit",
                 "full-url": "full URL including the protocol",
diff --git a/extensions/wikidata/module/scripts/warningsrenderer.js b/extensions/wikidata/module/scripts/warningsrenderer.js
index 3e5ab59b1..bab750a76 100644
--- a/extensions/wikidata/module/scripts/warningsrenderer.js
+++ b/extensions/wikidata/module/scripts/warningsrenderer.js
@@ -6,7 +6,6 @@ WarningsRenderer._renderEntity = function(entity) {
       entity.id = entity.value.id;
   }
   var id = entity.id;
-  console.log(entity);
   var is_new = entity.siteIri == "http://localhost/entity/";
   if (is_new) {
      id = $.i18n._('wikidata-preview')['new-id'];
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/editing/ConnectionManager.java b/extensions/wikidata/src/org/openrefine/wikidata/editing/ConnectionManager.java
index c63a5b2ea..f631be707 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/editing/ConnectionManager.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/editing/ConnectionManager.java
@@ -28,6 +28,8 @@ import java.io.IOException;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.wikidata.wdtk.wikibaseapi.ApiConnection;
 import org.wikidata.wdtk.wikibaseapi.LoginFailedException;
 
@@ -48,6 +50,8 @@ import com.google.refine.preference.PreferenceStore;
  */
 
 public class ConnectionManager {
+    
+    final static Logger logger = LoggerFactory.getLogger("connection_mananger");
 
     public static final String PREFERENCE_STORE_KEY = "wikidata_credentials";
 
@@ -76,7 +80,7 @@ public class ConnectionManager {
                 array.put(obj);
                 prefStore.put(PREFERENCE_STORE_KEY, array);
             } catch (JSONException e) {
-                e.printStackTrace();
+                logger.error(e.getMessage());
             }
         }
 
@@ -108,7 +112,7 @@ public class ConnectionManager {
             try {
                 return array.getJSONObject(0);
             } catch (JSONException e) {
-                e.printStackTrace();
+                logger.error(e.getMessage());
             }
         }
         return null;
@@ -121,7 +125,7 @@ public class ConnectionManager {
                 connection.logout();
                 connection = null;
             } catch (IOException e) {
-                e.printStackTrace();
+                logger.error(e.getMessage());
             }
         }
     }
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/exporters/QSValuePrinter.java b/extensions/wikidata/src/org/openrefine/wikidata/exporters/QSValuePrinter.java
index f43eec31d..c2903d876 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/exporters/QSValuePrinter.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/exporters/QSValuePrinter.java
@@ -51,9 +51,8 @@ public class QSValuePrinter implements ValueVisitor<String> {
 
     @Override
     public String visit(DatatypeIdValue value) {
-        // unsupported according to
-        // https://tools.wmflabs.org/wikidata-todo/quick_statements.php?
-        return null;
+        // impossible case (this is actually a bug in WDTK, DatatypeIdValue should not subclass Value)
+        throw new IllegalArgumentException();
     }
 
     @Override