diff --git a/CMakeLists.txt b/CMakeLists.txt
index c81581fe0f..efcc866195 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -93,6 +93,10 @@ endfunction()
 # Add the projects first so the Launcher can find them
 include(cmake/Projects.cmake)
 
+if(LY_EXTERNAL_SUBDIRS)
+    set_property(GLOBAL APPEND PROPERTY LY_EXTERNAL_SUBDIRS ${LY_EXTERNAL_SUBDIRS})
+endif()
+
 if(NOT INSTALLED_ENGINE)
     # Add external subdirectories listed in the engine.json. LY_EXTERNAL_SUBDIRS is a cache variable so the user can add extra
     # external subdirectories. This should go before adding the rest of the targets so the targets are availbe to the launcher.
diff --git a/cmake/Platform/Common/Install_common.cmake b/cmake/Platform/Common/Install_common.cmake
index 46130f1345..e42664c107 100644
--- a/cmake/Platform/Common/Install_common.cmake
+++ b/cmake/Platform/Common/Install_common.cmake
@@ -445,9 +445,10 @@ function(ly_setup_cmake_install)
         )
     endforeach()
 
-    # Transform the LY_EXTERNAL_SUBDIRS list into a json array
+    # Transform the LY_EXTERNAL_SUBDIRS global property list into a json array
     set(indent "        ")
-    foreach(external_subdir ${LY_EXTERNAL_SUBDIRS})
+    get_property(external_subdirs GLOBAL PROPERTY LY_EXTERNAL_SUBDIRS)
+    foreach(external_subdir ${external_subdirs})
         cmake_path(RELATIVE_PATH external_subdir BASE_DIRECTORY ${LY_ROOT_FOLDER} OUTPUT_VARIABLE engine_rel_external_subdir)
         list(APPEND relative_external_subdirs "\"${engine_rel_external_subdir}\"")
     endforeach()
@@ -639,7 +640,8 @@ function(ly_setup_assets)
     # the install layout from the root directory. Such as <external-subdirectory-root>/Cache.
     # This is also done to avoid globbing thousands of files in subdirectories that shouldn't
     # be processed.
-    foreach(gem_candidate_dir IN LISTS LY_EXTERNAL_SUBDIRS LY_PROJECTS)
+    get_property(external_subdirs GLOBAL PROPERTY LY_EXTERNAL_SUBDIRS)
+    foreach(gem_candidate_dir IN LISTS external_subdirs LY_PROJECTS)
         file(REAL_PATH ${gem_candidate_dir} gem_candidate_dir BASE_DIRECTORY ${LY_ROOT_FOLDER})
         # Don't recurse immediately in order to exclude transient source artifacts
         file(GLOB
diff --git a/scripts/build/Platform/Windows/build_windows.cmd b/scripts/build/Platform/Windows/build_windows.cmd
index 798550370f..c77c262692 100644
--- a/scripts/build/Platform/Windows/build_windows.cmd
+++ b/scripts/build/Platform/Windows/build_windows.cmd
@@ -9,6 +9,7 @@ REM
 
 SETLOCAL EnableDelayedExpansion
 CALL "%~dp0env_windows.cmd"
+IF NOT %ERRORLEVEL%==0 EXIT /b 1
 
 IF NOT EXIST "%OUTPUT_DIRECTORY%" (
     MKDIR %OUTPUT_DIRECTORY%.
@@ -21,7 +22,7 @@ ECHO [ci_build] cmake --version
 cmake --version
 IF ERRORLEVEL 1 (
     ECHO [ci_build] CMAKE not found!
-    exit /b 1
+    EXIT /b 1
 )
 
 REM Compute half the amount of processors so some jobs can run
@@ -47,14 +48,14 @@ IF NOT EXIST CMakeCache.txt (
     )
 )
 IF DEFINED RUN_CONFIGURE (
-    ECHO [ci_build] %CONFIGURE_CMD%
-    %CONFIGURE_CMD%
+    call ECHO [ci_build] %CONFIGURE_CMD%
+    call %CONFIGURE_CMD%
     IF NOT !ERRORLEVEL!==0 GOTO :error
     ECHO !CONFIGURE_CMD!> %LAST_CONFIGURE_CMD_FILE%
 )
 
-ECHO [ci_build] cmake --build . --target %CMAKE_TARGET% --config %CONFIGURATION% %CMAKE_BUILD_ARGS% -- %CMAKE_NATIVE_BUILD_ARGS%
-cmake --build . --target %CMAKE_TARGET% --config %CONFIGURATION% %CMAKE_BUILD_ARGS% -- %CMAKE_NATIVE_BUILD_ARGS%
+call ECHO [ci_build] cmake --build . --target %CMAKE_TARGET% --config %CONFIGURATION% %CMAKE_BUILD_ARGS% -- %CMAKE_NATIVE_BUILD_ARGS%
+call cmake --build . --target %CMAKE_TARGET% --config %CONFIGURATION% %CMAKE_BUILD_ARGS% -- %CMAKE_NATIVE_BUILD_ARGS%
 IF NOT %ERRORLEVEL%==0 GOTO :error
 
 POPD
diff --git a/scripts/build/Platform/Windows/env_windows.cmd b/scripts/build/Platform/Windows/env_windows.cmd
index 78b5ca6c1a..c6f46ef575 100644
--- a/scripts/build/Platform/Windows/env_windows.cmd
+++ b/scripts/build/Platform/Windows/env_windows.cmd
@@ -13,17 +13,21 @@ SETLOCAL EnableExtensions EnableDelayedExpansion
 where /Q cmake
 IF NOT %ERRORLEVEL%==0 (
     ECHO [ci_build] CMake not found
-    GOTO :error
-)
-
-IF NOT "%COMMAND_CWD%"=="" (
-    ECHO [ci_build] Changing CWD to %COMMAND_CWD%
-    CD %COMMAND_CWD%
+    GOTO :errorlocal
 )
 
 REM Ending the local environment to be able to propagate the TMP/TEMP variables to the calling script
 ENDLOCAL
 
+IF NOT "%COMMAND_CWD%"=="" (
+    call ECHO [ci_build] Changing CWD to %COMMAND_CWD%
+    call CD %COMMAND_CWD%
+    IF ERRORLEVEL 1 (
+        ECHO [ci_build] Failed to change directory to %COMMAND_CWD%
+        GOTO :error
+    )
+)
+
 REM Jenkins does not defined TMP
 IF "%TMP%"=="" (
     IF "%WORKSPACE%"=="" (
@@ -41,6 +45,7 @@ IF "%TMP%"=="" (
 
 EXIT /b 0
 
-:error
+:errorlocal
 ENDLOCAL
+:error
 EXIT /b 1
\ No newline at end of file