Enhance output documentation and error handling

Scripts/Features/Import-RegistryFile.ps1

@@ -1,4 +1,10 @@
-# Import & execute regfile
+<#
+    .SYNOPSIS
+    Imports and executes a registry file.
+
+    .OUTPUTS
+    System.Boolean. $true when the registry file is applied or previewed successfully; otherwise $false.
+#>
 function Import-RegistryFile {
     param (
         $message,

Scripts/Features/Invoke-Changes.ps1

@@ -198,11 +198,11 @@ function Invoke-FeatureUndo {
                 return $false
             }
             'EnableWindowsSandbox' {
-                Write-Host "> $($feature.ApplyUndoText)..."
+                Write-Host "> $undoText..."
                 return (Disable-WindowsFeature 'Containers-DisposableClientVM')
             }
             'EnableWindowsSubsystemForLinux' {
-                Write-Host "> $($feature.ApplyUndoText)..."
+                Write-Host "> $undoText..."
                 if (-not (Disable-WindowsFeature 'Microsoft-Windows-Subsystem-Linux')) { return $false }
                 return (Disable-WindowsFeature 'VirtualMachinePlatform')
             }
@@ -271,7 +271,10 @@ function Invoke-ApplyFeatures {
             & $script:ApplyProgressCallback $step $TotalSteps $displayName
         }
 
-        if (-not (Invoke-FeatureApply -FeatureId $featureId)) {
+        # Compare app-removal failure counts so a feature that only fails due to
+        # app removal isn't also double-reported as a feature failure.
+        $appRemovalFailuresBefore = $script:AppRemovalFailures
+        if ((-not (Invoke-FeatureApply -FeatureId $featureId)) -and ($script:AppRemovalFailures -eq $appRemovalFailuresBefore)) {
             $script:FeatureFailures++
         }
         Write-Host ""

Scripts/Features/Invoke-SystemRestorePoint.ps1

@@ -1,3 +1,10 @@
+<#
+    .SYNOPSIS
+    Creates a system restore point.
+
+    .OUTPUTS
+    System.Boolean. $true when a restore point is created; otherwise $false.
+#>
 function Invoke-SystemRestorePoint {
     $failed = $false
     $isSilent = ($script:Params -and $script:Params.ContainsKey('Silent')) -or $script:Silent

Scripts/Features/Replace-StartMenu.ps1

@@ -18,6 +18,9 @@
 
     .EXAMPLE
     Replace-StartMenuForAllUsers -startMenuTemplate "C:\CustomLayout.bin"
+
+    .OUTPUTS
+    System.Boolean. $true when all resolved profiles are updated or the change is previewed; otherwise $false.
 #>
 function Replace-StartMenuForAllUsers {
     param (
@@ -99,6 +102,9 @@ function Replace-StartMenuForAllUsers {
 
     .EXAMPLE
     Replace-StartMenu -startMenuBinFile "$env:LOCALAPPDATA\Packages\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\LocalState\start2.bin" -startMenuTemplate "C:\CustomLayout.bin"
+
+    .OUTPUTS
+    System.Boolean. $true when the template is valid and copied, or the change is previewed; otherwise $false.
 #>
 function Replace-StartMenu {
     param (

Scripts/Features/Set-StoreSearchSuggestions.ps1

@@ -10,6 +10,9 @@
 
     .EXAMPLE
     DisableStoreSearchSuggestionsForAllUsers
+
+    .OUTPUTS
+    System.Boolean. $true when a profile is processed and all ACL changes succeed; otherwise $false.
 #>
 function Set-StoreSearchSuggestionsDisabledForAllUsers {
     $success = $true
@@ -60,6 +63,9 @@ function Set-StoreSearchSuggestionsDisabledForAllUsers {
 
     .EXAMPLE
     DisableStoreSearchSuggestions -StoreAppsDatabase "$env:LOCALAPPDATA\Packages\Microsoft.WindowsStore_8wekyb3d8bbwe\LocalState\store.db"
+
+    .OUTPUTS
+    System.Boolean. $true when the database ACL is restricted or previewed; otherwise $false.
 #>
 function Set-StoreSearchSuggestionsDisabled {
     param (
@@ -115,6 +121,9 @@ function Set-StoreSearchSuggestionsDisabled {
 
     .EXAMPLE
     EnableStoreSearchSuggestionsForAllUsers
+
+    .OUTPUTS
+    System.Boolean. $true when a profile is processed and all ACL changes succeed; otherwise $false.
 #>
 function Set-StoreSearchSuggestionsEnabledForAllUsers {
     $success = $true
@@ -164,6 +173,9 @@ function Set-StoreSearchSuggestionsEnabledForAllUsers {
 
     .EXAMPLE
     EnableStoreSearchSuggestions -StoreAppsDatabase "$env:LOCALAPPDATA\Packages\Microsoft.WindowsStore_8wekyb3d8bbwe\LocalState\store.db"
+
+    .OUTPUTS
+    System.Boolean. $true when the deny ACL is removed, the database is absent, or the change is previewed; otherwise $false.
 #>
 function Set-StoreSearchSuggestionsEnabled {
     param (

Scripts/Features/Telemetry-ScheduledTasks.ps1

@@ -34,6 +34,9 @@ function Get-TelemetryScheduledTasks {
 
     .EXAMPLE
     Disable-TelemetryScheduledTasks
+
+    .OUTPUTS
+    System.Boolean. $true when every task is disabled, absent, already disabled, or previewed; otherwise $false.
 #>
 function Disable-TelemetryScheduledTasks {
     Write-Host "> Disabling telemetry scheduled tasks..."
@@ -97,6 +100,9 @@ function Disable-TelemetryScheduledTasks {
 
     .EXAMPLE
     Enable-TelemetryScheduledTasks
+
+    .OUTPUTS
+    System.Boolean. $true when every task is enabled, absent, already enabled, or previewed; otherwise $false.
 #>
 function Enable-TelemetryScheduledTasks {
     Write-Host "> Enabling telemetry scheduled tasks..."

Scripts/Features/Windows-OptionalFeatures.ps1

@@ -1,4 +1,10 @@
-# Enables a Windows optional feature and pipes its output to the console
+<#
+    .SYNOPSIS
+    Enables a Windows optional feature and pipes its output to the console.
+
+    .OUTPUTS
+    System.Boolean. $true when enabling succeeds or is previewed; otherwise $false.
+#>
 function Enable-WindowsFeature {
     param (
         [string]$FeatureName
@@ -44,7 +50,13 @@ function Enable-WindowsFeature {
     return $true
 }
 
-# Disables a Windows optional feature and pipes its output to the console
+<#
+    .SYNOPSIS
+    Disables a Windows optional feature and pipes its output to the console.
+
+    .OUTPUTS
+    System.Boolean. $true when disabling succeeds or is previewed; otherwise $false.
+#>
 function Disable-WindowsFeature {
     param (
         [string]$FeatureName