diff --git a/js/src/modals/ExecuteContract/executeContract.css b/js/src/modals/ExecuteContract/executeContract.css
index 55135a92e..a83b373ee 100644
--- a/js/src/modals/ExecuteContract/executeContract.css
+++ b/js/src/modals/ExecuteContract/executeContract.css
@@ -38,6 +38,7 @@
   border-radius: 0.5em;
   background: #f80;
   color: white;
+  font-size: 0.75em;
   padding: 0.75em;
   text-align: center;
 }
diff --git a/js/src/modals/ExecuteContract/executeContract.js b/js/src/modals/ExecuteContract/executeContract.js
index 8022690f5..1354e8543 100644
--- a/js/src/modals/ExecuteContract/executeContract.js
+++ b/js/src/modals/ExecuteContract/executeContract.js
@@ -71,6 +71,12 @@ class ExecuteContract extends Component {
     this.onFuncChange(null, functions[0]);
   }
 
+  componentWillReceiveProps (newProps) {
+    if (newProps.fromAddress !== this.props.fromAddress) {
+      this.estimateGas(newProps.fromAddress);
+    }
+  }
+
   render () {
     const { sending } = this.state;
 
@@ -164,8 +170,7 @@ class ExecuteContract extends Component {
   }
 
   onAmountChange = (amount) => {
-    this.estimateGas();
-    this.setState({ amount });
+    this.setState({ amount }, this.estimateGas);
   }
 
   onFuncChange = (event, func) => {
@@ -188,11 +193,10 @@ class ExecuteContract extends Component {
       }
     });
 
-    this.estimateGas();
     this.setState({
       func,
       values
-    });
+    }, this.estimateGas);
   }
 
   onValueChange = (event, index, _value) => {
@@ -218,29 +222,34 @@ class ExecuteContract extends Component {
     values[index] = value;
     valuesError[index] = valueError;
 
-    if (!valueError) {
-      this.estimateGas();
-    }
-
     this.setState({
       values: [].concat(values),
       valuesError: [].concat(valuesError)
+    }, () => {
+      if (!valueError) {
+        this.estimateGas();
+      }
     });
   }
 
-  estimateGas = () => {
+  estimateGas = (_fromAddress) => {
     const { api } = this.context;
     const { fromAddress, gasLimit } = this.props;
     const { amount, func, values } = this.state;
     const options = {
       gas: MAX_GAS_ESTIMATION,
-      from: fromAddress,
+      from: _fromAddress || fromAddress,
       value: api.util.toWei(amount || 0)
     };
 
+    if (!func) {
+      return;
+    }
+
     func
       .estimateGas(options, values)
       .then((gasEst) => {
+        console.log(gasEst.toFormat(0));
         const gas = gasEst.mul(1.2);
         let gasLimitError = null;
 
@@ -304,7 +313,7 @@ class ExecuteContract extends Component {
 }
 
 function mapStateToProps (state) {
-  const { gasLimit } = state.status;
+  const { gasLimit } = state.nodeStatus;
 
   return { gasLimit };
 }
diff --git a/js/src/modals/Transfer/errors.js b/js/src/modals/Transfer/errors.js
index c35d82636..3a6bd63ae 100644
--- a/js/src/modals/Transfer/errors.js
+++ b/js/src/modals/Transfer/errors.js
@@ -20,8 +20,8 @@ const ERRORS = {
   invalidAmount: 'the supplied amount should be a valid positive number',
   invalidDecimals: 'the supplied amount exceeds the allowed decimals',
   largeAmount: 'the transaction total is higher than the available balance',
-  gasException: 'the transaction indicates a thrown exception',
-  gasBlockLimit: 'the transaction will exceed the block gas limit'
+  gasException: 'the transaction will throw an exception with the current values',
+  gasBlockLimit: 'the transaction execution will exceed the block gas limit'
 };
 
 export default ERRORS;
diff --git a/js/src/modals/Transfer/transfer.css b/js/src/modals/Transfer/transfer.css
index 76f83c62b..b7f478b4f 100644
--- a/js/src/modals/Transfer/transfer.css
+++ b/js/src/modals/Transfer/transfer.css
@@ -157,6 +157,7 @@
   border-radius: 0.5em;
   background: #f80;
   color: white;
+  font-size: 0.75em;
   padding: 0.75em;
   text-align: center;
 }
diff --git a/js/src/modals/Transfer/transfer.js b/js/src/modals/Transfer/transfer.js
index 196307923..e906e45d7 100644
--- a/js/src/modals/Transfer/transfer.js
+++ b/js/src/modals/Transfer/transfer.js
@@ -681,7 +681,7 @@ class Transfer extends Component {
 }
 
 function mapStateToProps (state) {
-  const { gasLimit } = state.status;
+  const { gasLimit } = state.nodeStatus;
 
   return { gasLimit };
 }
diff --git a/js/src/util/constants.js b/js/src/util/constants.js
index 87ca59668..d0664d25e 100644
--- a/js/src/util/constants.js
+++ b/js/src/util/constants.js
@@ -19,7 +19,7 @@ const DEFAULT_GASPRICE = '20000000000';
 
 const MAX_GAS_ESTIMATION = '50000000';
 
-export default {
+export {
   DEFAULT_GAS,
   DEFAULT_GASPRICE,
   MAX_GAS_ESTIMATION