WiX Burn custom UI - wix

Question

I am trying to create a custom UI for WiX and Burn. I have followed some of the guides I've found, and so far I have a project that has the following, which inherits from BootstrapperApplication.
namespace MyBA
{
public class TestBA : BootstrapperApplication
{
protected override void Run()
{
MessageBox.Show("My BA is running");
this.Engine.Quit(0);
}
}
}
And in the AssemblyInfo.cs:
[assembly: BootstrapperApplication(typeof(TestBA))]
Then in my Bootstrapper project I have the following.
<?xml version="1.0" encoding="UTF-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi"
xmlns:util="http://schemas.microsoft.com/wix/UtilExtension">
<Bundle Name="MyApplication"
Version="1.0.0"
Manufacturer="Acme Ltd"
UpgradeCode="F84A4058-FDF6-4218-BCB5-12C811DA3C99"
Condition="NOT ((VersionNT = 600 AND ServicePackLevel >=2) OR (VersionNT >= 601))"
IconSourceFile="$(var.MyApplicationInstallerRequiredFiles.ProjectDir)logo.ico"
SplashScreenSourceFile="$(var.MyApplicationInstallerRequiredFiles.ProjectDir)Splashscreen.bmp"
DisableRepair="no"
DisableRemove="no"
DisableModify="no">
<WixVariable Id="WixMbaPrereqPackageId"
Value="Netfx4Full" />
<WixVariable Id="WixMbaPrereqLicenseUrl"
Value="NetfxLicense.rtf" />
<WixVariable Id="WixStdbaLicenseRtf"
Value="$(var.MyApplicationInstallerRequiredFiles.ProjectDir)Licence.en-gb.rtf" />
<WixVariable Id="WixStdbaLogo"
Value="$(var.MyApplicationInstallerRequiredFiles.ProjectDir)logoInstallSmall.bmp" />
<BootstrapperApplicationRef Id='ManagedBootstrapperApplicationHost'>
<Payload Name='BootstrapperCore.config'
SourceFile='$(var.MyApplicationInstallerRequiredFiles.ProjectDir)Bootstrapper\MyBA.BootstrapperCore.config' />
<Payload SourceFile='$(var.MyApplicationInstallerRequiredFiles.ProjectDir)Bootstrapper\MyBA.dll' />
</BootstrapperApplicationRef>
<Chain>
<PackageGroupRef Id="MyApplicationPackage" />
</Chain>
</Bundle>
</Wix>
and I have added MyBA.BootstrapperCore.config
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<sectionGroup name="wix.bootstrapper"
type="Microsoft.Tools.WindowsInstallerXml.Bootstrapper.BootstrapperSectionGroup, BootstrapperCore">
<section name="host"
type="Microsoft.Tools.WindowsInstallerXml.Bootstrapper.HostSection, BootstrapperCore" />
</sectionGroup>
</configSections>
<startup useLegacyV2RuntimeActivationPolicy="true">
<supportedRuntime version="v4.0" />
</startup>
<wix.bootstrapper>
<host assemblyName="MyBA">
<supportedFramework version="v4\Full" />
<supportedFramework version="v4\Client" />
</host>
</wix.bootstrapper>
</configuration>
However, whenever I run the Setup.exe for the bootstrapper, I get the splashscreen appear briefly, but nothing else. If I look in the %TEMP% at the logs there is the following
[0A00:0424][2011-11-02T15:52:08]: Burn v3.6.2221.0, path: C:\MyApplication\dev\source\Bootstrapper1\bin\Debug\Setup.exe, cmdline: ''
[0A00:0424][2011-11-02T15:52:08]: Setting string variable 'WixBundleName' to value 'MyApplication'
[0A00:0424][2011-11-02T15:52:08]: Setting string variable 'WixBundleLog' to value 'C:\Users\AppData\Local\Temp\MyApplication_20111102155208.log'
[0A00:0424][2011-11-02T15:52:08]: Condition 'NOT ((VersionNT = 600 AND ServicePackLevel >=2) OR (VersionNT >= 601))' evaluates to true.
[0A00:0424][2011-11-02T15:52:08]: Setting string variable 'WixBundleOriginalSource' to value 'C:\MyApplication\dev\source\Bootstrapper1\bin\Debug\Setup.exe'
[0A00:0424][2011-11-02T15:52:08]: Loading managed bootstrapper application.
[0A00:0424][2011-11-02T15:52:08]: Error 0x80131040: Failed to create the managed bootstrapper application.
[0A00:0424][2011-11-02T15:52:08]: Error 0x80131040: Failed to create UX.
[0A00:0424][2011-11-02T15:52:08]: Error 0x80131040: Failed to load UX.
[0A00:0424][2011-11-02T15:52:08]: Error 0x80131040: Failed while running
[0A00:0424][2011-11-02T15:52:08]: Error 0x80131040: Failed to run per-user mode.
Why is this happening and why are the above errors occurring?

Answer 1

If you look at the source code for the WixBA, they declare a global Threading.Dispatcher, and then in the overridden Run() method, there is the following line:
Threading.Dispatcher.Run();
I had similar issues, and similarly adding the Threading.Dispatcher to my bootstrapper application fixed them.
Also, if your Bootstrapper Application depends on any other dlls, you need to include them as a <Payload/> under your <BootstrapperApplicationRef/>.