Error importing ARM64 BSP

[dvescovi1]

I generated an ARM64 workspace using this IoT ADK add on kit.
like:
PS C:\iot-adk-addonkit\Workspace>new-ws C:\RPI\iotcore\myrpi4arm64workspace Contoso arm64 New IoTWorkSpace available at C:\RPI\iotcore\myrpi4arm64workspace for arm64 Opening workspace : C:\RPI\iotcore\myrpi4arm64workspace\IoTWorkspace.xml arm64 IoT Core kit version 10.0.17763.253 found Corekit install path found OK ADK_VERSION : 10.0.17763.1 IOTCORE_VER : 10.0.17763.253 BSP_VERSION : 10.0.0.0 ADDONKITVER : 7.0.210203.1200 HostOS Info : Microsoft Windows 10 Pro - 10.0.19043 - en-US Error: Host OS Enterprise Edition required for using Security functions such as Device Guard IOTWKSPACE : C:\RPI\iotcore\myrpi4arm64workspace OEM_NAME : Contoso BSP_ARCH : arm64 BSPPKG_DIR : C:\RPI\iotcore\myrpi4arm64workspace\Build\arm64\pkgs MSPKG_DIR : C:\Program Files (x86)\Windows Kits\10\MSPackages\Retail\arm64\fre Copying Registry.Version Copying Custom.Cmd Copying Provisioning.Auto Copying OEM.Sample Copying Device.SystemInformation Copying DeviceLayout.GPT4GB Copying DeviceLayout.GPT8GB-R Copying DeviceLayout.MBR4GB Copying DeviceLayout.MBR8GB-R Workspace ready! IoTCorePShell arm64 10.0.0.0 Test PS C:\RPI\iotcore\myrpi4arm64workspace>importpkg * Copying Appx.Certs Copying Custom.BCD Copying Custom.OOBEApp Copying Custom.Settings Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\Packages\Device.SystemInformation already exist. Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\Packages\DeviceLayout.GPT4GB already exist. Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\Packages\DeviceLayout.GPT8GB-R already exist. Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\Packages\DeviceLayout.MBR4GB already exist. Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\Packages\DeviceLayout.MBR8GB-R already exist. Copying Recovery.GPT-BCD Copying Recovery.GPT-BcdEdit Copying Recovery.MBR-BCD Copying Recovery.MBR-BcdEdit Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\Packages\Registry.Version already exist. Copying Security.BitLocker Copying Security.DeviceGuard Copying Security.DeviceGuardTest Copying Security.RootCerts Copying Security.SecureBoot Copying Security.SecureBootTest Copying Settings.HotKey Warning: C:\RPI\iotcore\myrpi4arm64workspace\Source-arm64\Packages\OEM.Sample already exist. Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\ProdPackages\Custom.Cmd already exist. Warning: C:\RPI\iotcore\myrpi4arm64workspace\Common\ProdPackages\Provisioning.Auto already exist. Copying Recovery.WinPE IoTCorePShell arm64 10.0.0.0 Test PS C:\RPI\iotcore\myrpi4arm64workspace>importbsp RPi c:\Release\RPi_BSP_ARM64_Release.zip Extracting BSP zip into the temporary directory C:\RPI\iotcore\myrpi4arm64workspace\BSPDIR Processing C:\RPI\iotcore\myrpi4arm64workspace\BSPDIR\RPi Error: Incorrect BSP arch. Found arm, expected arm64 IoTCorePShell arm64 10.0.0.0 Test PS C:\RPI\iotcore\myrpi4arm64workspace>

This looks like it created my ARM64 workspace correctly.
I then imported all packages using the "importpkg *"
This also seems to have worked fine.
I then tried to import my "built for ARM64" BSP and got the failure "Incorrect BSP arch. Found arm, expected arm64"
I am not sure this is an ADK import problem or the fact I used the "binexport.ps1" script from the github
https://github.com/raspberrypi/windows-drivers

That script seems to have a hard coded path at line 30:
$bindir = $RootDir + "build\bcm2836\ARM\$buildconfig\"
I changed the "ARM" to "ARM64" and was able to generate to RPi_BSP_Release.zip but it has problems importing