diff --git a/example/bin/taskdialog.exe.manifest b/example/bin/taskdialog.exe.manifest
index e702396e18..e5a62c5ece 100644
--- a/example/bin/taskdialog.exe.manifest
+++ b/example/bin/taskdialog.exe.manifest
@@ -3,7 +3,7 @@
     <assemblyIdentity
         type="win32"
         name="win32.taskdialog"
-        processorArchitecture="amd64" 
+        processorArchitecture="amd64"
         version="1.0.0.0"
     />
     <description>taskdialog</description>
@@ -18,7 +18,7 @@
             <!-- Windows 7 -->
             <supportedOS Id="{35138b9a-5d96-4fbd-8e2d-a2440225f93a}"/>
             <!-- Windows Vista -->
-            <supportedOS Id="{e2011457-1546-43c5-a5fe-008deee3d3f0}"/> 
+            <supportedOS Id="{e2011457-1546-43c5-a5fe-008deee3d3f0}"/>
         </application>
     </compatibility>
     <dependency>
@@ -45,8 +45,8 @@
                 <requestedExecutionLevel
                     level="asInvoker"
                     uiAccess="false"
-                />   
+                />
             </requestedPrivileges>
         </security>
     </trustInfo>
-</assembly>
\ No newline at end of file
+</assembly>
diff --git a/example/taskdialog.dart b/example/taskdialog.dart
index 92c4ffc838..afc9c59802 100644
--- a/example/taskdialog.dart
+++ b/example/taskdialog.dart
@@ -13,6 +13,11 @@
 // taskdialog.exe.manifest. Place the compiled taskdialog.exe in the same folder
 // as the manifest and then when you run this it should display two task dialog
 // samples.
+//
+// If that doesn't work, make sure that external manifests are enabled in the
+// registry. This can be done by running the following command in an elevated
+// command prompt:
+//   REG ADD "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\SideBySide" /v PreferExternalManifest /t REG_DWORD /d 1 /f
 
 import 'dart:ffi';
 
@@ -20,18 +25,22 @@ import 'package:ffi/ffi.dart';
 import 'package:win32/win32.dart';
 
 void showSimpleTaskDialog() {
-  final windowTitle = 'Dart TaskDialog Sample'.toNativeUtf16();
-  final mainInstruction = 'Please read this important message'.toNativeUtf16();
-  final content = 'Task dialogs are great for sharing a longer string of '
-          'explanatory content, where you need a user to read an instruction '
-          'before making a decision. Of course, you cannot guarantee that the '
-          "user will actually read the text, so it's important that you also "
-          'provide an undo function for when the wrong choice is selected.'
-      .toNativeUtf16();
-  final buttonSelected = calloc<Int32>();
+  using((arena) {
+    final windowTitle =
+        'Dart TaskDialog Sample'.toNativeUtf16(allocator: arena);
+    final mainInstruction =
+        'Please read this important message'.toNativeUtf16(allocator: arena);
+    final content = 'Task dialogs are great for sharing a longer string of '
+            'explanatory content, where you need a user to read an instruction '
+            'before making a decision. Of course, you cannot guarantee that '
+            'the user will actually read the text, so it\'s important that you '
+            'also provide an undo function for when the wrong choice is '
+            'selected.'
+        .toNativeUtf16(allocator: arena);
+    final buttonSelected = arena<Int32>();
 
-  try {
-    final hr = TaskDialog(
+    try {
+      final hr = TaskDialog(
         NULL,
         NULL,
         windowTitle,
@@ -40,83 +49,83 @@ void showSimpleTaskDialog() {
         TASKDIALOG_COMMON_BUTTON_FLAGS.TDCBF_OK_BUTTON |
             TASKDIALOG_COMMON_BUTTON_FLAGS.TDCBF_CANCEL_BUTTON,
         TD_INFORMATION_ICON,
-        buttonSelected);
-    if (SUCCEEDED(hr)) {
-      switch (buttonSelected.value) {
-        case MESSAGEBOX_RESULT.IDOK:
-          print('User clicked on the OK button.');
-        default:
-          print('User canceled the task dialog.');
+        buttonSelected,
+      );
+      if (SUCCEEDED(hr)) {
+        switch (buttonSelected.value) {
+          case MESSAGEBOX_RESULT.IDOK:
+            print('User clicked on the OK button.');
+          default:
+            print('User canceled the task dialog.');
+        }
       }
+    } on ArgumentError {
+      print(
+        'If you see an error "Failed to lookup symbol", it\'s likely because '
+        'the app manifest declaring a dependency on comctl32.dll v6 is '
+        'missing.\n\nSee the comment at the top of the sample source code.\n',
+      );
+      rethrow;
     }
-    // ignore: avoid_catching_errors
-  } on ArgumentError {
-    print('If you see an error "Failed to lookup symbol", it\'s likely because '
-        'the app manifest\ndeclaring a dependency on comctl32.dll v6 is '
-        'missing.\n\nSee the comment at the top of the sample source code.\n');
-    rethrow;
-  } finally {
-    free(windowTitle);
-    free(mainInstruction);
-    free(content);
-  }
+  });
 }
 
 void showCustomTaskDialog() {
-  // Note that this example does not explicitly free allocated memory, since it
-  // returns quickly to the command prompt. As part of a real app, you'd
-  // certainly want to free each string here.
-  final buttonSelected = calloc<Int32>();
-
-  final buttons = calloc<TASKDIALOG_BUTTON>(2);
-  buttons[0]
-    ..nButtonID = 100
-    ..pszButtonText =
-        'Take the blue pill\nThe story ends, you wake up in your bed and '
-                'believe whatever you want to believe.'
-            .toNativeUtf16();
-  buttons[1]
-    ..nButtonID = 101
-    ..pszButtonText =
-        'Take the red pill\nYou stay in Wonderland, and I show you how deep '
-                'the rabbit hole goes.'
-            .toNativeUtf16();
+  using((arena) {
+    final buttonSelected = arena<Int32>();
 
-  const matrixDescription =
-      'In The Matrix, the main character Neo is offered  the choice between '
-      'a red pill and a blue pill by rebel leader Morpheus. The red pill '
-      'represents an uncertain future: it would free him from the enslaving '
-      'control of the machine-generated dream world and allow him to escape '
-      'into the real world, but living the "truth of reality" is harsher and '
-      'more difficult. On the other hand, the blue pill represents a '
-      'beautiful prison: it would lead him back to ignorance, living in '
-      'confined comfort without want or fear within '
-      'the simulated reality of the Matrix.';
+    const numberOfButtons = 2;
+    final buttons = arena<TASKDIALOG_BUTTON>(numberOfButtons);
+    buttons[0]
+      ..nButtonID = 100
+      ..pszButtonText =
+          'Take the blue pill\nThe story ends, you wake up in your bed and '
+                  'believe whatever you want to believe.'
+              .toNativeUtf16(allocator: arena);
+    buttons[1]
+      ..nButtonID = 101
+      ..pszButtonText =
+          'Take the red pill\nYou stay in Wonderland, and I show you how deep '
+                  'the rabbit hole goes.'
+              .toNativeUtf16(allocator: arena);
 
-  final config = calloc<TASKDIALOGCONFIG>()
-    ..ref.cbSize = sizeOf<TASKDIALOGCONFIG>()
-    ..ref.pszWindowTitle = 'TaskDialogIndirect Sample'.toNativeUtf16()
-    ..ref.pszMainInstruction = 'Which pill will you take?'.toNativeUtf16()
-    ..ref.pszContent =
-        'This is your last chance. There is no turning back.'.toNativeUtf16()
-    ..ref.hMainIcon = TD_WARNING_ICON.address
-    ..ref.pszCollapsedControlText = 'See more details.'.toNativeUtf16()
-    ..ref.pszExpandedControlText = matrixDescription.toNativeUtf16()
-    ..ref.dwFlags = TASKDIALOG_FLAGS.TDF_USE_COMMAND_LINKS
-    ..ref.cButtons = 2
-    ..ref.pButtons = buttons;
+    const matrixDescription =
+        'In The Matrix, the main character Neo is offered the choice between a '
+        'red pill and a blue pill by rebel leader Morpheus. The red pill '
+        'represents an uncertain future: it would free him from the enslaving '
+        'control of the machine-generated dream world and allow him to escape '
+        'into the real world, but living the "truth of reality" is harsher and '
+        'more difficult. On the other hand, the blue pill represents a '
+        'beautiful prison: it would lead him back to ignorance, living in '
+        'confined comfort without want or fear within the simulated reality of '
+        'the Matrix.';
 
-  final hr = TaskDialogIndirect(config, buttonSelected, nullptr, nullptr);
+    final config = arena<TASKDIALOGCONFIG>();
+    config.ref
+      ..cbSize = sizeOf<TASKDIALOGCONFIG>()
+      ..pszWindowTitle =
+          'TaskDialogIndirect Sample'.toNativeUtf16(allocator: arena)
+      ..pszMainInstruction =
+          'Which pill will you take?'.toNativeUtf16(allocator: arena)
+      ..pszContent = 'This is your last chance. There is no turning back.'
+          .toNativeUtf16(allocator: arena)
+      ..hMainIcon = TD_WARNING_ICON.address
+      ..pszExpandedInformation =
+          matrixDescription.toNativeUtf16(allocator: arena)
+      ..dwFlags = TASKDIALOG_FLAGS.TDF_USE_COMMAND_LINKS |
+          TASKDIALOG_FLAGS.TDF_EXPAND_FOOTER_AREA
+      ..cButtons = numberOfButtons
+      ..pButtons = buttons;
 
-  if (SUCCEEDED(hr)) {
-    if (buttonSelected.value == 100) {
-      print('Ignorance is bliss.');
-    } else {
-      print("I've been expecting you, Mr Anderson.");
+    final hr = TaskDialogIndirect(config, buttonSelected, nullptr, nullptr);
+    if (SUCCEEDED(hr)) {
+      if (buttonSelected.value == 100) {
+        print('Ignorance is bliss.');
+      } else {
+        print("I've been expecting you, Mr. Anderson.");
+      }
     }
-  } else {
-    print('that failed.');
-  }
+  });
 }
 
 void main() {