diff --git a/numass-core/src/main/java/inr/numass/NumassEnvelopeType.java b/numass-core/src/main/java/inr/numass/NumassEnvelopeType.java
index d0654532..0d69571d 100644
--- a/numass-core/src/main/java/inr/numass/NumassEnvelopeType.java
+++ b/numass-core/src/main/java/inr/numass/NumassEnvelopeType.java
@@ -16,6 +16,9 @@ import static hep.dataforge.io.envelopes.DefaultEnvelopeType.DEFAULT_ENVELOPE_TY
  */
 public class NumassEnvelopeType implements EnvelopeType {
 
+    public static final byte[] LEGACY_START_SEQUENCE = {'#', '!'};
+    public static final byte[] LEGACY_END_SEQUENCE = {'!', '#', '\r', '\n'};
+
     @Override
     public int getCode() {
         return DEFAULT_ENVELOPE_TYPE;
@@ -41,18 +44,15 @@ public class NumassEnvelopeType implements EnvelopeType {
         return new DefaultEnvelopeWriter(this, MetaType.resolve(properties));
     }
 
-    private static class LegacyTag extends EnvelopeTag {
-        private final byte[] START_SEQUENCE = {'#', '!'};
-        private final byte[] END_SEQUENCE = {'!', '#', '\r', '\n'};
-
+    public static class LegacyTag extends EnvelopeTag {
         @Override
         protected byte[] getStartSequence() {
-            return START_SEQUENCE;
+            return LEGACY_START_SEQUENCE;
         }
 
         @Override
         protected byte[] getEndSequence() {
-            return END_SEQUENCE;
+            return LEGACY_END_SEQUENCE;
         }
 
         /**
diff --git a/numass-core/src/main/java/inr/numass/data/legacy/NumassFileEnvelope.java b/numass-core/src/main/java/inr/numass/data/legacy/NumassFileEnvelope.java
new file mode 100644
index 00000000..11eda987
--- /dev/null
+++ b/numass-core/src/main/java/inr/numass/data/legacy/NumassFileEnvelope.java
@@ -0,0 +1,44 @@
+package inr.numass.data.legacy;
+
+import hep.dataforge.io.envelopes.EnvelopeTag;
+import hep.dataforge.storage.filestorage.FileEnvelope;
+import inr.numass.NumassEnvelopeType;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.SeekableByteChannel;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+
+import static inr.numass.NumassEnvelopeType.LEGACY_START_SEQUENCE;
+import static java.nio.file.StandardOpenOption.READ;
+
+public class NumassFileEnvelope extends FileEnvelope {
+
+    public static FileEnvelope open(Path path, boolean readOnly) {
+        if (!Files.exists(path)) {
+            throw new RuntimeException("File envelope does not exist");
+        }
+        try (SeekableByteChannel channel = Files.newByteChannel(path, READ)) {
+            ByteBuffer header = ByteBuffer.allocate(2);
+            channel.read(header);
+            if(Arrays.equals(header.array(),LEGACY_START_SEQUENCE)){
+                return new NumassFileEnvelope(path,readOnly);
+            } else {
+                return FileEnvelope.open(path, readOnly);
+            }
+        } catch (IOException e) {
+            throw new RuntimeException("Failed to open file envelope", e);
+        }
+    }
+
+    private NumassFileEnvelope(Path path, boolean readOnly) {
+        super(path, readOnly);
+    }
+
+    @Override
+    protected EnvelopeTag buildTag(){
+        return new NumassEnvelopeType.LegacyTag();
+    }
+}
diff --git a/numass-core/src/main/java/inr/numass/data/storage/NumassDataLoader.java b/numass-core/src/main/java/inr/numass/data/storage/NumassDataLoader.java
index 7f4f7832..f411870e 100644
--- a/numass-core/src/main/java/inr/numass/data/storage/NumassDataLoader.java
+++ b/numass-core/src/main/java/inr/numass/data/storage/NumassDataLoader.java
@@ -24,13 +24,13 @@ import hep.dataforge.meta.MetaBuilder;
 import hep.dataforge.providers.Provider;
 import hep.dataforge.storage.api.ObjectLoader;
 import hep.dataforge.storage.api.Storage;
-import hep.dataforge.storage.filestorage.FileEnvelope;
 import hep.dataforge.storage.filestorage.FileStorage;
 import hep.dataforge.storage.loaders.AbstractLoader;
 import hep.dataforge.tables.Table;
 import hep.dataforge.values.Value;
 import inr.numass.data.api.NumassPoint;
 import inr.numass.data.api.NumassSet;
+import inr.numass.data.legacy.NumassFileEnvelope;
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
@@ -87,7 +87,7 @@ public class NumassDataLoader extends AbstractLoader implements ObjectLoader<Env
                     || fileName.startsWith(POINT_FRAGMENT_NAME);
         }).forEach(file -> {
             try {
-                items.put(FileStorage.entryName(file), () -> FileEnvelope.open(file, true));
+                items.put(FileStorage.entryName(file), () -> NumassFileEnvelope.open(file, true));
             } catch (Exception ex) {
                 LoggerFactory.getLogger(NumassDataLoader.class)
                         .error("Can't load numass data directory " + FileStorage.entryName(directory), ex);
diff --git a/numass-main/src/main/java/inr/numass/actions/MonitorCorrectAction.java b/numass-main/src/main/java/inr/numass/actions/MonitorCorrectAction.java
index 4a7a4979..739e4dea 100644
--- a/numass-main/src/main/java/inr/numass/actions/MonitorCorrectAction.java
+++ b/numass-main/src/main/java/inr/numass/actions/MonitorCorrectAction.java
@@ -27,6 +27,8 @@ import hep.dataforge.tables.Table;
 import hep.dataforge.tables.ValueMap;
 import hep.dataforge.values.Value;
 import hep.dataforge.values.Values;
+import inr.numass.data.api.NumassAnalyzer;
+import inr.numass.data.api.NumassPoint;
 import inr.numass.utils.NumassUtils;
 import javafx.util.Pair;
 import org.apache.commons.math3.analysis.interpolation.SplineInterpolator;
@@ -40,6 +42,7 @@ import java.util.TreeMap;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 import static hep.dataforge.values.ValueType.NUMBER;
+import static inr.numass.data.analyzers.AbstractAnalyzer.TIME_KEY;
 
 /**
  * @author Darksnake
@@ -50,7 +53,7 @@ import static hep.dataforge.values.ValueType.NUMBER;
 @ValueDef(name = "calculateRelative", info = "Calculate count rate relative to average monitor point", def = "false")
 public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
 
-    private static final String[] monitorNames = {"Timestamp", "Total", "CR", "CRerr"};
+    //private static final String[] monitorNames = {"timestamp", NumassAnalyzer.COUNT_KEY, NumassAnalyzer.COUNT_RATE_KEY, NumassAnalyzer.COUNT_RATE_KEY};
 
     CopyOnWriteArrayList<Values> monitorPoints = new CopyOnWriteArrayList<>();
     //FIXME remove from state
@@ -67,16 +70,16 @@ public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
         }
         double norm = 0;
         double totalAv = 0;
-        String head = "";
-        head += String.format("%20s\t%10s\t%s%n", "Timestamp", "Total", "CR in window");
+        StringBuilder head = new StringBuilder();
+        head.append(String.format("%20s\t%10s\t%s%n", "timestamp", "Count", "CR in window"));
         for (Values dp : index.values()) {
-            head += String.format("%20s\t%10d\t%g%n", getTime(dp).toString(), getTotal(dp), getCR(dp));
+            head.append(String.format("%20s\t%10d\t%g%n", getTime(dp).toString(), getTotal(dp), getCR(dp)));
             norm += getCR(dp) / index.size();
             totalAv += getTotal(dp) / index.size();
             monitorPoints.add(dp);
         }
 
-        head += String.format("%20s\t%10g\t%g%n", "Average", totalAv, norm);
+        head.append(String.format("%20s\t%10g\t%g%n", "Average", totalAv, norm));
 
         List<Values> dataList = new ArrayList<>();
 
@@ -93,7 +96,7 @@ public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
                 double corrFactor = corr.getKey();
                 double corrErr = corr.getValue();
 
-                double pointErr = dp.getValue("CRerr").doubleValue() / getCR(dp);
+                double pointErr = dp.getValue(NumassAnalyzer.COUNT_RATE_ERROR_KEY).doubleValue() / getCR(dp);
                 double err = Math.sqrt(corrErr * corrErr + pointErr * pointErr) * getCR(dp);
 
                 if (dp.getNames().contains("Monitor")) {
@@ -102,23 +105,22 @@ public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
                     pb.putValue("Monitor", corrFactor);
                 }
 
-                pb.putValue("CR", Value.of(dp.getValue("CR").doubleValue() / corrFactor));
-                pb.putValue("Window", Value.of(dp.getValue("Window").doubleValue() / corrFactor));
-                pb.putValue("CRerr", Value.of(err));
+                pb.putValue(NumassAnalyzer.COUNT_RATE_KEY, Value.of(dp.getValue(NumassAnalyzer.COUNT_RATE_KEY).doubleValue() / corrFactor));
+                pb.putValue(NumassAnalyzer.COUNT_RATE_ERROR_KEY, Value.of(err));
             } else {
-                double corrFactor = dp.getValue("CR").doubleValue() / norm;
+                double corrFactor = dp.getValue(NumassAnalyzer.COUNT_RATE_KEY).doubleValue() / norm;
                 if (dp.getNames().contains("Monitor")) {
                     pb.putValue("Monitor", Value.of(dp.getValue("Monitor").doubleValue() / corrFactor));
                 } else {
                     pb.putValue("Monitor", corrFactor);
                 }
-                pb.putValue("CR", norm);
+                pb.putValue(NumassAnalyzer.COUNT_RATE_KEY, norm);
 
             }
 
             if (meta.getBoolean("calculateRelative", false)) {
-                pb.putValue("relCR", pb.build().getValue("CR").doubleValue() / norm);
-                pb.putValue("relCRerr", pb.build().getValue("CRerr").doubleValue() / norm);
+                pb.putValue("relCR", pb.build().getValue(NumassAnalyzer.COUNT_RATE_KEY).doubleValue() / norm);
+                pb.putValue("relCRerr", pb.build().getValue(NumassAnalyzer.COUNT_RATE_ERROR_KEY).doubleValue() / norm);
             }
 
             dataList.add(pb.build());
@@ -155,7 +157,7 @@ public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
 
         PolynomialSplineFunction corrFunc = new SplineInterpolator().interpolate(xs, ys);
         if (corrFunc.isValidPoint(time)) {
-            double averageErr = index.values().stream().mapToDouble(p -> p.getDouble("CRerr")).average().getAsDouble();
+            double averageErr = index.values().stream().mapToDouble(p -> p.getDouble(NumassAnalyzer.COUNT_RATE_ERROR_KEY)).average().getAsDouble();
             return new Pair<>(corrFunc.value(time), averageErr / norm / 2d);
         } else {
             return new Pair<>(1d, 0d);
@@ -184,7 +186,7 @@ public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
         }
 
         double corrFactor = (getCR(previousMonitor.getValue()) * (1 - p) + getCR(nextMonitor.getValue()) * p) / norm;
-        double corrErr = previousMonitor.getValue().getValue("CRerr").doubleValue() / getCR(previousMonitor.getValue()) / Math.sqrt(2);
+        double corrErr = previousMonitor.getValue().getValue(NumassAnalyzer.COUNT_RATE_ERROR_KEY).doubleValue() / getCR(previousMonitor.getValue()) / Math.sqrt(2);
         return new Pair<>(corrFactor, corrErr);
     }
 
@@ -205,19 +207,19 @@ public class MonitorCorrectAction extends OneToOneAction<Table, Table> {
     }
 
     private boolean isMonitorPoint(double monitor, Values point) {
-        return point.getValue("Uset").doubleValue() == monitor;
+        return point.getValue(NumassPoint.HV_KEY).doubleValue() == monitor;
     }
 
     private Instant getTime(Values point) {
-        return point.getValue("Timestamp").timeValue();
+        return point.getValue(TIME_KEY).timeValue();
     }
 
     private int getTotal(Values point) {
-        return point.getValue("Total").intValue();
+        return point.getValue(NumassAnalyzer.COUNT_KEY).intValue();
     }
 
     private double getCR(Values point) {
-        return point.getValue("CR").doubleValue();
+        return point.getValue(NumassAnalyzer.COUNT_RATE_KEY).doubleValue();
     }
 
     private TreeMap<Instant, Values> getMonitorIndex(double monitor, Iterable<Values> data) {
diff --git a/numass-main/src/main/java/inr/numass/tasks/NumassSubstractEmptySourceTask.java b/numass-main/src/main/java/inr/numass/tasks/NumassSubstractEmptySourceTask.java
index 1220e122..800a6402 100644
--- a/numass-main/src/main/java/inr/numass/tasks/NumassSubstractEmptySourceTask.java
+++ b/numass-main/src/main/java/inr/numass/tasks/NumassSubstractEmptySourceTask.java
@@ -64,19 +64,19 @@ public class NumassSubstractEmptySourceTask extends AbstractTask<Table> {
         return builder.build();
     }
 
+
     @Override
-    protected TaskModel transformModel(TaskModel model) {
-        Meta modelMeta = model.meta();
-        model.dependsOn("prepare", modelMeta, "prepare");
+    protected void updateModel(TaskModel.Builder model, Meta meta) {
+        model.dependsOn("prepare", meta, "prepare");
         MetaBuilder emptyCfg = new MetaBuilder("prepare")
-                .setNode(modelMeta.getMeta("prepare"))
-                .setNode("data", modelMeta.getMeta("empty"))
-                .setNode(new MetaBuilder("merge").setValue("mergeName", model.meta().getName() + ".empty"));
+                .setNode(meta.getMeta("prepare"))
+                .setNode("data", meta.getMeta("empty"))
+                .setNode(new MetaBuilder("merge").setValue("mergeName", model.getName() + ".empty"));
         model.dependsOn("prepare", emptyCfg, "empty");
-        return model;
     }
 
 
+
     private Data<? extends Table> subtract(Data<? extends Table> mergeData, Data<? extends Table> emptyData) {
         return DataUtils.combine(mergeData, emptyData, Table.class, mergeData.meta(), (BiFunction<Table, Table, Table>) this::subtract);
     }
diff --git a/numass-viewer/src/main/resources/fxml/MainView.fxml b/numass-viewer/src/main/resources/fxml/MainView.fxml
index 1878aa18..aece1e31 100644
--- a/numass-viewer/src/main/resources/fxml/MainView.fxml
+++ b/numass-viewer/src/main/resources/fxml/MainView.fxml
@@ -37,7 +37,7 @@ limitations under the License.
                         <Insets left="10.0" />
                      </padding></Label>
                   <Pane HBox.hgrow="ALWAYS" />
-                  <ToggleButton fx:id="processManagerButton" mnemonicParsing="false" text="ProcessManager" />
+                  <!--<ToggleButton fx:id="processManagerButton" mnemonicParsing="false" text="ProcessManager" />-->
                   <ToggleButton fx:id="consoleButton" contentDisplay="CENTER" mnemonicParsing="false" text="Console" />
               </items>
             </ToolBar>