diff --git a/.efrocachemap b/.efrocachemap
index 23b3ad75..64bfe1b9 100644
--- a/.efrocachemap
+++ b/.efrocachemap
@@ -3934,26 +3934,26 @@
   "assets/build/windows/Win32/vcruntime140d.dll": "https://files.ballistica.net/cache/ba1/50/8d/bc2600ac9491f1b14d659709451f",
   "ballisticacore-windows/Generic/BallisticaCore.ico": "https://files.ballistica.net/cache/ba1/89/c0/e32c7d2a35dc9aef57cc73b0911a",
   "ballisticacore-windows/build/Debug_Win32/BallisticaCoreGenericInternal.lib": "https://files.ballistica.net/cache/ba1/c0/40/9fdab51c7fa8fba261618358f928",
-  "build/prefab/full/linux_arm64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/12/21/1f7c97804b69d8b86b384a1e84bc",
+  "build/prefab/full/linux_arm64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/74/f5/cc58a7bcf2e1615e0fa3bd6d5d0d",
   "build/prefab/full/linux_arm64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/74/1d/fc9e33e565475daaac80da5252f0",
-  "build/prefab/full/linux_arm64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/fc/9c/6d1124445b4e1eccaaff2f3267db",
-  "build/prefab/full/linux_arm64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/d4/c1/4c40dce3437c7db6d4d829dd40a2",
-  "build/prefab/full/linux_x86_64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/17/e0/bca1901d13afd756c02d98224017",
+  "build/prefab/full/linux_arm64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/2f/01/da01f984477a5c174187a6574b1c",
+  "build/prefab/full/linux_arm64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/b9/48/9ebca395c79a78a73d886f2cf79e",
+  "build/prefab/full/linux_x86_64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/ae/67/58655e787268082e7e1502d1a787",
   "build/prefab/full/linux_x86_64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/9c/7b/ac1a200be0f37078af0991faca3b",
-  "build/prefab/full/linux_x86_64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/8c/db/34bcecb347bf98e48a12064748a6",
-  "build/prefab/full/linux_x86_64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/0c/18/1b58ff9ba35df5b2ee0283f1cb8f",
-  "build/prefab/full/mac_arm64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/c1/1e/ebc55dc85b5db4e1b2aadc871e4c",
-  "build/prefab/full/mac_arm64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/02/64/9acb11a2e2d0bfa61ca6b4dcd932",
-  "build/prefab/full/mac_arm64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/cd/57/16915454124808b10fca758bbafb",
-  "build/prefab/full/mac_arm64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/33/6d/cfe199fcb64ea199339ad3feca05",
-  "build/prefab/full/mac_x86_64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/77/a3/6dfc684a930e4971f68c5b33a32a",
-  "build/prefab/full/mac_x86_64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/4d/41/a28b6e8e65329bd93625afe1d861",
-  "build/prefab/full/mac_x86_64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/44/36/e8d6968d65daad9d20eb209d6018",
-  "build/prefab/full/mac_x86_64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/a5/03/ab15f420cdbbf0986c386cf796a9",
-  "build/prefab/full/windows_x86_gui/debug/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/42/52/fdcdd78c71fe91e66365189169d6",
-  "build/prefab/full/windows_x86_gui/release/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/62/0b/727e271829ddfc995756c4d256e6",
-  "build/prefab/full/windows_x86_server/debug/dist/BallisticaCoreHeadless.exe": "https://files.ballistica.net/cache/ba1/5d/d9/c9662534ea22a671d6e6c3955230",
-  "build/prefab/full/windows_x86_server/release/dist/BallisticaCoreHeadless.exe": "https://files.ballistica.net/cache/ba1/b4/4a/4e2a80edf6ed933f6e96de08defb",
+  "build/prefab/full/linux_x86_64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/14/57/c84a61d1fc1696964619dbdee287",
+  "build/prefab/full/linux_x86_64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/a3/a1/79b409f8281bf8ecb4cca37863b8",
+  "build/prefab/full/mac_arm64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/5b/79/22275b3d5ca8448bfa483f3b9b34",
+  "build/prefab/full/mac_arm64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/a3/90/ff8b627c70adc3d588e3c89d0c15",
+  "build/prefab/full/mac_arm64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/c9/2c/82c01a070a2980159d91ec741707",
+  "build/prefab/full/mac_arm64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/b9/aa/b7dbcd94a062856664359ff68a6d",
+  "build/prefab/full/mac_x86_64_gui/debug/ballisticacore": "https://files.ballistica.net/cache/ba1/d7/c0/9a394fdaeab40c66235590de6dba",
+  "build/prefab/full/mac_x86_64_gui/release/ballisticacore": "https://files.ballistica.net/cache/ba1/65/24/c3d7e4552caeb825e7be6dd2ac4f",
+  "build/prefab/full/mac_x86_64_server/debug/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/dc/45/96900412696ba52e7057951735bf",
+  "build/prefab/full/mac_x86_64_server/release/dist/ballisticacore_headless": "https://files.ballistica.net/cache/ba1/2f/61/31fcd63001ff4bfebb9896e8f227",
+  "build/prefab/full/windows_x86_gui/debug/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/61/65/e7811e813273ec28b741a07bbfcf",
+  "build/prefab/full/windows_x86_gui/release/BallisticaCore.exe": "https://files.ballistica.net/cache/ba1/77/f0/b8ebac6ebc3e95592b47f93f6c5c",
+  "build/prefab/full/windows_x86_server/debug/dist/BallisticaCoreHeadless.exe": "https://files.ballistica.net/cache/ba1/67/37/ae25e8bb39288bf2ad27d2265954",
+  "build/prefab/full/windows_x86_server/release/dist/BallisticaCoreHeadless.exe": "https://files.ballistica.net/cache/ba1/41/9c/e8d910d7b498051103143e5ef8c2",
   "build/prefab/lib/linux_arm64_gui/debug/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/0f/fc/cd29b733f94c767231f5d3e3b49b",
   "build/prefab/lib/linux_arm64_gui/release/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/b2/bb/dd0a84740970e62169e8690c0906",
   "build/prefab/lib/linux_arm64_server/debug/libballisticacore_internal.a": "https://files.ballistica.net/cache/ba1/72/a8/bdf8597296d539357b344f75082d",
diff --git a/Makefile b/Makefile
index bb4ff7d8..7dd103a1 100644
--- a/Makefile
+++ b/Makefile
@@ -907,14 +907,14 @@ _cmake-simple-ci-server-build:
 
 _windows-wsl-build:
 	${WIN_MSBUILD_EXE_B} \
-  ${shell wslpath -m -a \
+  ${shell tools/pcommand wsl_to_escaped_win_path \
   ballisticacore-windows/${WINPRJ}/BallisticaCore${WINPRJ}.vcxproj} \
   -target:Build -property:Configuration=${WINCFG} \
   -property:Platform=${WINPLT} ${VISUAL_STUDIO_VERSION}
 
 _windows-wsl-rebuild:
 	${WIN_MSBUILD_EXE_B} \
-  ${shell wslpath -m -a \
+  ${shell tools/pcommand wsl_to_escaped_win_path \
   ballisticacore-windows/${WINPRJ}/BallisticaCore${WINPRJ}.vcxproj} \
   -target:Rebuild -property:Configuration=${WINCFG} \
   -property:Platform=${WINPLT} ${VISUAL_STUDIO_VERSION}
diff --git a/src/ballistica/ballistica.cc b/src/ballistica/ballistica.cc
index dd3cb37f..23f0008b 100644
--- a/src/ballistica/ballistica.cc
+++ b/src/ballistica/ballistica.cc
@@ -20,8 +20,8 @@
 
 namespace ballistica {
 
-// These are set automatically via script; don't edit them here.
-const int kAppBuildNumber = 20371;
+// These are set automatically via script; don't modify them here.
+const int kAppBuildNumber = 20372;
 const char* kAppVersion = "1.6.4";
 
 // Our standalone globals.
diff --git a/tools/batools/pcommand.py b/tools/batools/pcommand.py
index ade57da0..9282cbae 100644
--- a/tools/batools/pcommand.py
+++ b/tools/batools/pcommand.py
@@ -474,6 +474,25 @@ def checkenv() -> None:
     batools.build.checkenv()
 
 
+def wsl_to_escaped_win_path() -> None:
+    """Forward escape slashes in a provided win path arg."""
+    import subprocess
+    from efro.error import CleanError
+    if len(sys.argv) != 3:
+        raise CleanError('Expected 1 path arg.')
+    try:
+        out = subprocess.run(['wslpath', '-w', '-a', sys.argv[2]],
+                             capture_output=True,
+                             check=True)
+    except Exception:
+        # This gets used in a makefile so our returncode is ignored;
+        # try to convey failure in other ways.
+        print('wsl_to_escaped_win_path_error_occurred', end='')
+        return
+
+    print(out.stdout.decode().strip().replace('\\', '\\\\'), end='')
+
+
 def ensure_build_platform() -> None:
     """Ensure we are building on a particular platform."""
     import batools.build
diff --git a/tools/pcommand b/tools/pcommand
index 32f9efa0..5e145b8b 100755
--- a/tools/pcommand
+++ b/tools/pcommand
@@ -38,7 +38,7 @@ from batools.pcommand import (
     make_prefab, update_makebob, lazybuild, android_archive_unstripped_libs,
     efro_gradle, stage_assets, update_assets_makefile, update_project,
     update_cmake_prefab_lib, cmake_prep_dir, gen_binding_code,
-    gen_flat_data_code)
+    gen_flat_data_code, wsl_to_escaped_win_path)
 # pylint: enable=unused-import
 
 if TYPE_CHECKING: