diff --git a/numass-core/src/main/java/inr/numass/storage/NumassDataLoader.java b/numass-core/src/main/java/inr/numass/storage/NumassDataLoader.java
index 4ccd13a4..48a49a2d 100644
--- a/numass-core/src/main/java/inr/numass/storage/NumassDataLoader.java
+++ b/numass-core/src/main/java/inr/numass/storage/NumassDataLoader.java
@@ -15,7 +15,6 @@
  */
 package inr.numass.storage;
 
-import hep.dataforge.context.Global;
 import hep.dataforge.data.Data;
 import hep.dataforge.exceptions.StorageException;
 import hep.dataforge.io.ColumnedDataReader;
@@ -136,7 +135,7 @@ public class NumassDataLoader extends AbstractLoader implements ObjectLoader<Env
 
     private static Envelope readFile(FileObject file) {
         //VFS file reading seems to work badly in parallel
-        synchronized (Global.instance()) {
+        //synchronized (Global.instance()) {
             String fileName = file.getName().getBaseName();
             if (fileName.equals(META_FRAGMENT_NAME)
                     || fileName.equals(HV_FRAGMENT_NAME)
@@ -150,7 +149,7 @@ public class NumassDataLoader extends AbstractLoader implements ObjectLoader<Env
             } else {
                 return null;
             }
-        }
+        //}
     }
 
     /**
diff --git a/numass-main/src/main/java/inr/numass/tasks/NumassFitScanSummaryTask.java b/numass-main/src/main/java/inr/numass/tasks/NumassFitScanSummaryTask.java
index dccbe48f..b964aeaa 100644
--- a/numass-main/src/main/java/inr/numass/tasks/NumassFitScanSummaryTask.java
+++ b/numass-main/src/main/java/inr/numass/tasks/NumassFitScanSummaryTask.java
@@ -13,7 +13,7 @@ import hep.dataforge.data.DataSet;
 import hep.dataforge.description.TypedActionDef;
 import hep.dataforge.io.ColumnedDataWriter;
 import hep.dataforge.meta.Laminate;
-import hep.dataforge.stat.fit.FitState;
+import hep.dataforge.stat.fit.FitResult;
 import hep.dataforge.stat.fit.ParamSet;
 import hep.dataforge.stat.fit.UpperLimitGenerator;
 import hep.dataforge.tables.ListTable;
@@ -34,8 +34,8 @@ public class NumassFitScanSummaryTask extends AbstractTask<Table> {
     @Override
     protected DataNode<Table> run(TaskModel model, DataNode<?> data) {
         DataSet.Builder<Table> builder = DataSet.builder(Table.class);
-        Action<FitState, Table> action = new FitSummaryAction();
-        DataNode<FitState> input = data.getCheckedNode("fitscan", FitState.class);
+        Action<FitResult, Table> action = new FitSummaryAction();
+        DataNode<FitResult> input = data.getCheckedNode("fitscan", FitResult.class);
         input.nodeStream().filter(it -> it.dataSize(false) > 0).forEach(node ->
                 builder.putData(node.getName(), action.run(model.getContext(), node, model.meta()).getData())
         );
@@ -54,11 +54,11 @@ public class NumassFitScanSummaryTask extends AbstractTask<Table> {
         return "scansum";
     }
 
-    @TypedActionDef(name = "sterileSummary", inputType = FitState.class, outputType = Table.class)
-    private class FitSummaryAction extends ManyToOneAction<FitState, Table> {
+    @TypedActionDef(name = "sterileSummary", inputType = FitResult.class, outputType = Table.class)
+    private class FitSummaryAction extends ManyToOneAction<FitResult, Table> {
 
         @Override
-        protected Table execute(Context context, String nodeName, Map<String, FitState> input, Laminate meta) {
+        protected Table execute(Context context, String nodeName, Map<String, FitResult> input, Laminate meta) {
             ListTable.Builder builder = new ListTable.Builder("m", "U2", "U2err", "U2limit", "E0", "trap");
             input.forEach((key, fitRes) -> {
                 ParamSet pars = fitRes.getParameters();
diff --git a/numass-main/src/main/java/inr/numass/tasks/NumassFitScanTask.java b/numass-main/src/main/java/inr/numass/tasks/NumassFitScanTask.java
index 3e89265c..29e41882 100644
--- a/numass-main/src/main/java/inr/numass/tasks/NumassFitScanTask.java
+++ b/numass-main/src/main/java/inr/numass/tasks/NumassFitScanTask.java
@@ -17,6 +17,7 @@ import hep.dataforge.values.Value;
 import hep.dataforge.workspace.AbstractTask;
 import hep.dataforge.workspace.TaskModel;
 
+import java.util.Objects;
 import java.util.stream.Collectors;
 
 /**
@@ -56,16 +57,18 @@ public class NumassFitScanTask extends AbstractTask<FitResult> {
             for (int i = 0; i < scanValues.listValue().size(); i++) {
                 Value val = scanValues.listValue().get(i);
                 MetaBuilder overrideMeta = new MetaBuilder(fitConfig);
-                overrideMeta.setValue("@resultName", String.format("%s[%s=%s]", table.getName(), scanParameter, val.stringValue()));
+
+                String resultName = String.format("%s[%s=%s]", table.getName(), scanParameter, val.stringValue());
+//                overrideMeta.setValue("@resultName", String.format("%s[%s=%s]", table.getName(), scanParameter, val.stringValue()));
 
                 if (overrideMeta.hasMeta("params." + scanParameter)) {
                     overrideMeta.setValue("params." + scanParameter + ".value", val);
                 } else {
                     overrideMeta.getMetaList("params.param").stream()
-                            .filter(par -> par.getString("name") == scanParameter).forEach(par -> par.setValue("value", val));
+                            .filter(par -> Objects.equals(par.getString("name"), scanParameter)).forEach(par -> par.setValue("value", val));
                 }
 //                Data<Table> newData = new Data<Table>(data.getGoal(),data.type(),overrideMeta);
-                DataNode<FitResult> node = action.run(model.getContext(), DataNode.of("fit_" + i, table, Meta.empty()), overrideMeta);
+                DataNode<FitResult> node = action.run(model.getContext(), DataNode.of(resultName, table, Meta.empty()), overrideMeta);
                 resultBuilder.putData(table.getName() + ".fit_" + i, node.getData());
             }
         });
@@ -80,6 +83,8 @@ public class NumassFitScanTask extends AbstractTask<FitResult> {
         MetaBuilder metaBuilder = new MetaBuilder(model.meta()).removeNode("fit").removeNode("scan");
         if (model.meta().hasMeta("filter")) {
             model.dependsOn("filter", metaBuilder.build(), "prepare");
+        } else if (model.meta().hasMeta("empty")) {
+            model.dependsOn("substractEmpty", metaBuilder.build(), "prepare");
         } else {
             model.dependsOn("prepare", metaBuilder.build(), "prepare");
         }