diff --git a/app/js/components/edit-bar.js b/app/js/components/edit-bar.js
index 1fa1e6e..cbc75bc 100644
--- a/app/js/components/edit-bar.js
+++ b/app/js/components/edit-bar.js
@@ -32,7 +32,7 @@ class EditBar extends React.Component {
 
       for (var i = 0; i < this.props.selected.length; i++) {
 
-        if(this.props.tilesets.get(this.props.selected[i]).type != this.props.tilesets.get(this.props.selected[0]).type){
+        if(this.props.tilesets[this.props.selected[i]].type != this.props.tilesets[this.props.selected[0]].type){
 
           allTheSame = false;
 
@@ -41,11 +41,11 @@ class EditBar extends React.Component {
       }
 
       if(this.props.selected != null && this.props.selected > -1){
-        defaultSelectValue = this.props.tilesets.get(this.props.selected[0]).type;
+        defaultSelectValue = this.props.tilesets[this.props.selected[0]].type;
       } else {
 
         if(allTheSame == true){
-          defaultSelectValue = this.props.tilesets.get(this.props.selected[0]).type;
+          defaultSelectValue = this.props.tilesets[this.props.selected[0]].type;
         } else {
           defaultSelectValue = -1;
         }
diff --git a/app/js/components/main-canvas.js b/app/js/components/main-canvas.js
index 6c39a12..fb8bd61 100644
--- a/app/js/components/main-canvas.js
+++ b/app/js/components/main-canvas.js
@@ -44,11 +44,14 @@ class MainCanvas extends React.Component {
     var width = 0;
     var height = 0;
 
-    for(var tileset of this.props.tilesets.values()) {
+    for (var key in this.props.tilesets) {
+      if (this.props.tilesets.hasOwnProperty(key)) {
 
-      width = Math.max(width, tilesetTemplate[tileset.type].width * tileset.tileSize);
-      height = tileset.y + tileset.height;
+        var tileset = this.props.tilesets[key];
+        width = Math.max(width, tilesetTemplate[tileset.type].width * tileset.tileSize);
+        height = tileset.y + tileset.height;
 
+      }
     }
 
     this.canvas.width = width;
@@ -64,20 +67,25 @@ class MainCanvas extends React.Component {
 
     this.setCanvasSize();
 
-    for(var tileset of this.props.tilesets.values()) {
+    for (var key in this.props.tilesets) {
+
+      if (this.props.tilesets.hasOwnProperty(key)) {
+
+        var tileset = this.props.tilesets[key];
 
+        for (h = 0; h < tilesetTemplate[tileset.type].height * 2; h++) {
 
-      for (h = 0; h < tilesetTemplate[tileset.type].height * 2; h++) {
+          for (w = 0; w < tilesetTemplate[tileset.type].width * 2; w++) {
 
-        for (w = 0; w < tilesetTemplate[tileset.type].width * 2; w++) {
+            this.drawTile(
+              tileset.img, //sprite
+              tileset.x + (w * (tileset.tileSize / 2)), //x
+              tileset.y + (h * (tileset.tileSize / 2)), //y
+              tilesetTemplate[tileset.type].map[(tilesetTemplate[tileset.type].width * 2) * h + w] - 1, //type
+              tileset.tileSize //tileSize
+            );
 
-          this.drawTile(
-            tileset.img, //sprite
-            tileset.x + (w * (tileset.tileSize / 2)), //x
-            tileset.y + (h * (tileset.tileSize / 2)), //y
-            tilesetTemplate[tileset.type].map[(tilesetTemplate[tileset.type].width * 2) * h + w] - 1, //type
-            tileset.tileSize //tileSize
-          );
+          }
 
         }
 
@@ -89,9 +97,9 @@ class MainCanvas extends React.Component {
 
   render() {
 
-    if(this.ctx && this.props.tilesets.size > 0)
+    if(this.ctx && Object.keys(this.props.tilesets).length > 0)
       this.generateTileset();
-    else if(this.ctx && this.props.tilesets.size == 0)
+    else if(this.ctx && Object.keys(this.props.tilesets).length == 0)
       this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
 
     return (
diff --git a/app/js/components/tileset-bases-container.js b/app/js/components/tileset-bases-container.js
index a05b61d..9faee93 100644
--- a/app/js/components/tileset-bases-container.js
+++ b/app/js/components/tileset-bases-container.js
@@ -9,17 +9,20 @@ class TilesetBaseContainer extends React.Component {
 
     var tilesetItens = [];
 
-    for(var tileset of this.props.tilesets.values()) {
+    for (var key in this.props.tilesets) {
+      if (this.props.tilesets.hasOwnProperty(key)) {
+        var tileset = this.props.tilesets[key];
 
-      var selected = false;
+        var selected = false;
 
-      if(_.indexOf(this.props.selected, tileset.id) > -1){
-        selected = true;
-      }
+        if(_.indexOf(this.props.selected, tileset.id) > -1){
+          selected = true;
+        }
 
-      tilesetItens.push(<TilesetBase selected={selected} select={this.props.selectTileset} close={this.props.onClose} dataUri={tileset.uri} id={tileset.id} key={tileset.id} />);
+        tilesetItens.push(<TilesetBase selected={selected} select={this.props.selectTileset} close={this.props.onClose} dataUri={tileset.uri} id={tileset.id} key={tileset.id} />);
 
-    };
+      }
+    }
 
     return (
       <div className="tileset-bases">
diff --git a/app/js/main.js b/app/js/main.js
index fc62bab..3a36d4d 100644
--- a/app/js/main.js
+++ b/app/js/main.js
@@ -7,7 +7,6 @@ var MainCanvas = require('./components/main-canvas.js');
 var EditBar = require('./components/edit-bar.js');
 var ConfigBar = require('./components/config-bar.js');
 
-
 var tilesetTemplate = require('./template.js');
 
 class TilesetGen extends React.Component{
@@ -17,7 +16,7 @@ class TilesetGen extends React.Component{
     super(props);
 
     this.state = {
-      tilesets: new Map(),
+      tilesets: {},
       selectedTileSet: [],
       currentID: 0,
       lastHeight: 0,
@@ -54,17 +53,17 @@ class TilesetGen extends React.Component{
 
           var y = 0;
 
-          if(tilesets.size === 1){
+          if(Object.keys(tilesets).length === 1){
 
             y = this.state.lastHeight;
 
-          } else if(tilesets.size >= 1){
+          } else if(Object.keys(tilesets).length >= 1){
 
             y = this.state.lastY + this.state.lastHeight;
 
           }
 
-          tilesets.set(ID, {
+          tilesets[ID] = {
             uri: dataUri,
             img: img,
             id: ID,
@@ -74,10 +73,10 @@ class TilesetGen extends React.Component{
             y: y,
             width: 0,
             height: tilesetTemplate[0].height * (img.naturalWidth / 2)
-          });
+          };
 
           this.setState({
-            lastHeight: tilesets.get(ID).height,
+            lastHeight: tilesets[ID].height,
             lastY: y,
             tilesets: tilesets,
             currentID: this.state.currentID
@@ -96,25 +95,29 @@ class TilesetGen extends React.Component{
 
     var y = 0, height = 0, lastY = 0;
 
-    tilesets.forEach(function(tileset){
+    for (var key in this.state.tilesets) {
+      if (this.state.tilesets.hasOwnProperty(key)) {
 
-      y = 0;
+        var tileset = this.state.tilesets[key];
 
-      if(tilesets.size === 1){
+        y = 0;
 
-        y = height;
+        if(Object.keys(tilesets).length === 1){
 
-      } else if(tilesets.size > 1){
+          y = height;
 
-        y = lastY + height;
+        } else if(Object.keys(tilesets).length > 1){
 
-      }
+          y = lastY + height;
 
-      lastY = y;
-      tileset.y = y;
-      height = tileset.height;
+        }
 
-    });
+        lastY = y;
+        tileset.y = y;
+        height = tileset.height;
+
+      }
+    };
 
     this.setState({
       lastHeight: height,
@@ -127,7 +130,7 @@ class TilesetGen extends React.Component{
 
     for (var i = 0; i < this.state.selectedTileSet.length; i++) {
 
-      this.state.tilesets.delete( this.state.selectedTileSet[i] );
+      this.state.tilesets = _.omit(this.state.tilesets, this.state.selectedTileSet[i]);
 
     }
 
@@ -146,8 +149,8 @@ class TilesetGen extends React.Component{
 
     var tilesets = this.state.tilesets, y = 0;
 
-    tilesets.get(id).type = +type;
-    tilesets.get(id).height = tilesetTemplate[tilesets.get(id).type].height * tilesets.get(id).tileSize;
+    tilesets[id].type = +type;
+    tilesets[id].height = tilesetTemplate[tilesets[id].type].height * tilesets[id].tileSize;
 
     this.recalcYPosition(tilesets);
 
@@ -175,9 +178,14 @@ class TilesetGen extends React.Component{
 
     this.state.selectedTileSet.length = 0;
 
-    for(var tileset of this.state.tilesets.values()) {
+    for (var key in this.state.tilesets) {
+
+      if (this.state.tilesets.hasOwnProperty(key)) {
 
-      this.state.selectedTileSet.push(tileset.id);
+        var tileset = this.state.tilesets[key];
+        this.state.selectedTileSet.push(tileset.id);
+
+      }
 
     }