diff --git a/html/src/main/java/com/agifans/agile/gwt/GwtDialogHandler.java b/html/src/main/java/com/agifans/agile/gwt/GwtDialogHandler.java
index 403ab77..57f9899 100644
--- a/html/src/main/java/com/agifans/agile/gwt/GwtDialogHandler.java
+++ b/html/src/main/java/com/agifans/agile/gwt/GwtDialogHandler.java
@@ -12,9 +12,11 @@
 import com.agifans.agile.ui.ImportTypeResponseHandler;
 import com.agifans.agile.ui.OpenFileResponseHandler;
 import com.agifans.agile.ui.TextInputResponseHandler;
+import com.agifans.agile.worker.Worker;
 import com.akjava.gwt.jszip.JSFile;
 import com.akjava.gwt.jszip.JSZip;
 import com.badlogic.gdx.Gdx;
+import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.core.client.JsArrayString;
 import com.google.gwt.typedarrays.shared.ArrayBuffer;
 import com.google.gwt.typedarrays.shared.Int8Array;
@@ -29,6 +31,8 @@ public class GwtDialogHandler implements DialogHandler {
     
     private GameFileMapEncoder gameFileMapEncoder;
     
+    private Worker worker;
+    
     private boolean dialogOpen;
     
     /**
@@ -37,6 +41,10 @@ public class GwtDialogHandler implements DialogHandler {
     public GwtDialogHandler() {
         gameFileMapEncoder = new GameFileMapEncoder();
         opfsGameFiles = new OPFSGameFiles();
+        
+        // The same worker script is used for importing game data as is used for 
+        // the interpreter but they are run in two different running web workers.
+        worker = Worker.create("worker/worker.nocache.js");
     }
 
     @Override
@@ -215,7 +223,8 @@ public void onFileResultsReady(GwtOpenFileResult[] openFileResultArray) {
 
                         // Use GameFileMapEncoder to encode to single ArrayBuffer and store in OPFS.
                         ArrayBuffer fullGameBuffer = gameFileMapEncoder.encodeGameFileMap(gameFilesMap);
-                        opfsGameFiles.writeGameFilesData(opfsDirectoryName, fullGameBuffer);
+                        worker.postArrayBufferAndObject(
+                                "ImportGame", fullGameBuffer, createDirectoryNameObject(opfsDirectoryName));
                         
                         openFileResponseHandler.openFileResult(true, opfsDirectoryName, gameName, detection.gameId);
                         
@@ -234,6 +243,10 @@ public void onFileResultsReady(GwtOpenFileResult[] openFileResultArray) {
         });
     }
     
+    private native JavaScriptObject createDirectoryNameObject(String directoryName)/*-{
+        return { directoryName: directoryName };
+    }-*/;
+    
     private final native String slugify(String str)/*-{
         return String(str)
             .normalize('NFKD')
diff --git a/html/src/main/java/com/agifans/agile/worker/AgileWebWorker.java b/html/src/main/java/com/agifans/agile/worker/AgileWebWorker.java
index ed19336..82969eb 100644
--- a/html/src/main/java/com/agifans/agile/worker/AgileWebWorker.java
+++ b/html/src/main/java/com/agifans/agile/worker/AgileWebWorker.java
@@ -10,6 +10,7 @@
 import com.agifans.agile.gwt.GwtUserInput;
 import com.agifans.agile.gwt.GwtVariableData;
 import com.agifans.agile.gwt.GwtWavePlayer;
+import com.agifans.agile.gwt.OPFSGameFiles;
 import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.typedarrays.shared.ArrayBuffer;
 import com.google.gwt.webworker.client.DedicatedWorkerEntryPoint;
@@ -72,6 +73,11 @@ public class AgileWebWorker extends DedicatedWorkerEntryPoint implements Message
      */
     private Interpreter interpreter;
     
+    /**
+     * Used to store game data files.
+     */
+    private OPFSGameFiles opfsGameFiles;
+    
     /**
      * Incoming messages from the UI thread are for two purposes: One is to set things 
      * up, and then once both sides are up and running, the UI thread then starts sending
@@ -88,6 +94,12 @@ public void onMessage(MessageEvent event) {
         JavaScriptObject eventObject = event.getDataAsObject();
         
         switch (getEventType(eventObject)) {
+            case "ImportGame":
+                ArrayBuffer importGameDataBuffer = getArrayBuffer(eventObject);
+                String opfsDirectionName = getNestedString(eventObject, "directoryName");
+                opfsGameFiles.writeGameFilesData(opfsDirectionName, importGameDataBuffer);
+                break;
+        
             case "Initialise":
                 JavaScriptObject keyPressQueueSAB = getNestedObject(eventObject, "keyPressQueueSAB");
                 JavaScriptObject keysSAB = getNestedObject(eventObject, "keysSAB");
@@ -106,7 +118,6 @@ public void onMessage(MessageEvent event) {
                 GameFileMapEncoder gameFileMapDecoder = new GameFileMapEncoder();
                 gameLoader = new GwtGameLoader(pixelData);
                 Game game = gameLoader.loadGame(gameFileMapDecoder.decodeGameFileMap(gameDataBuffer));
-                // TODO: This won't work for fan games that haven't set the game ID.
                 savedGameStore.initialise(game.gameId);
                 interpreter = new Interpreter(
                         game, userInput, wavePlayer, savedGameStore, 
@@ -166,6 +177,7 @@ protected final void setOnMessage(MessageHandler messageHandler) {
     @Override
     public void onWorkerLoad() {
         this.scope = DedicatedWorkerGlobalScope.get();
+        this.opfsGameFiles = new OPFSGameFiles();
         
         this.importScript("/opfs-saved-games.js");
         
diff --git a/html/src/main/java/com/agifans/agile/worker/Worker.java b/html/src/main/java/com/agifans/agile/worker/Worker.java
index cbfad55..bd9b88d 100644
--- a/html/src/main/java/com/agifans/agile/worker/Worker.java
+++ b/html/src/main/java/com/agifans/agile/worker/Worker.java
@@ -53,6 +53,18 @@ public final native void postArrayBuffer(String name, ArrayBuffer buffer) /*-{
         this.postMessage({name: name, buffer: buffer}, [buffer]);
     }-*/;
     
+    /**
+     * This method can be used to transfer an ArrayBuffer along with a normal JavaScript
+     * object in the same message.
+     * 
+     * @param name The name of the object. Used for identification of the object.
+     * @param buffer The JS ArrayByffer to send in the postMessage call.
+     * @param object The normal JavaScript object to send with the ArrayBuffer.
+     */
+    public final native void postArrayBufferAndObject(String name, ArrayBuffer buffer, JavaScriptObject object) /*-{
+        this.postMessage({name: name, buffer: buffer, object: object}, [buffer]);
+    }-*/;
+    
     private static void onMessageImpl(MessageHandler messageHandler, MessageEvent event) {
         UncaughtExceptionHandler ueh = GWT.getUncaughtExceptionHandler();
         if (ueh != null) {