diff --git a/src/main/java/com/metaweb/gridworks/model/Cell.java b/src/main/java/com/metaweb/gridworks/model/Cell.java
index f626ec455..451c98dd0 100644
--- a/src/main/java/com/metaweb/gridworks/model/Cell.java
+++ b/src/main/java/com/metaweb/gridworks/model/Cell.java
@@ -130,9 +130,9 @@ public class Cell implements HasFields, Jsonizable {
                 if (token == JsonToken.VALUE_STRING) {
                     value = jp.getText();
                 } else if (token == JsonToken.VALUE_NUMBER_INT) {
-                    value = jp.getIntValue();
+                    value = jp.getLongValue();
                 } else if (token == JsonToken.VALUE_NUMBER_FLOAT) {
-                    value = jp.getFloatValue();
+                    value = jp.getDoubleValue();
                 } else if (token == JsonToken.VALUE_TRUE) {
                     value = true;
                 } else if (token == JsonToken.VALUE_FALSE) {
diff --git a/src/main/java/com/metaweb/gridworks/model/Recon.java b/src/main/java/com/metaweb/gridworks/model/Recon.java
index 6876d8f1e..27b30c573 100644
--- a/src/main/java/com/metaweb/gridworks/model/Recon.java
+++ b/src/main/java/com/metaweb/gridworks/model/Recon.java
@@ -279,9 +279,9 @@ public class Recon implements HasFields, Jsonizable {
                         if (token == JsonToken.VALUE_STRING) {
                             recon.features[feature++] = jp.getText();
                         } else if (token == JsonToken.VALUE_NUMBER_INT) {
-                            recon.features[feature++] = jp.getIntValue();
+                            recon.features[feature++] = jp.getLongValue();
                         } else if (token == JsonToken.VALUE_NUMBER_FLOAT) {
-                            recon.features[feature++] = jp.getFloatValue();
+                            recon.features[feature++] = jp.getDoubleValue();
                         } else if (token == JsonToken.VALUE_FALSE) {
                             recon.features[feature++] = false;
                         } else if (token == JsonToken.VALUE_TRUE) {
diff --git a/src/main/java/com/metaweb/gridworks/operations/MassEditOperation.java b/src/main/java/com/metaweb/gridworks/operations/MassEditOperation.java
index 98289905c..668a2f83b 100644
--- a/src/main/java/com/metaweb/gridworks/operations/MassEditOperation.java
+++ b/src/main/java/com/metaweb/gridworks/operations/MassEditOperation.java
@@ -54,7 +54,8 @@ public class MassEditOperation extends EngineDependentMassCellOperation {
     }
     
     static public AbstractOperation reconstruct(Project project, JSONObject obj) throws Exception {
-        JSONObject engineConfig = obj.getJSONObject("engineConfig");
+        JSONObject engineConfig = obj.has("engineConfig") && !obj.isNull("engineConfig") ?
+                obj.getJSONObject("engineConfig") : null;
         
         return new MassEditOperation(
             engineConfig,