Cygwin X crashing on -multiwindow option

A shot in the dark, but can anyone point me in the right direction? Thought this might be similar to this bug (http://cygwin.1069669.n5.nabble.com/1-9-2-0-Xwin-SIGSEGV-when-font-server-should-be-queried-td65322.html), but it's years old, and my build is the latest.

Thanks.

% X --version 
Welcome to the XWin X Server
Vendor: The Cygwin/X Project
Release: 1.13.3.0
OS: CYGWIN_NT-6.1-WOW64 US-SEA-R82K76F 1.7.17(0.262/5/3) 2012-10-19 14:39 i686
OS: Windows 7  [Windows NT 6.1 build 7600] (WoW64)
Package: version 1.13.3-1 built 2013-03-09

% X 
// loads just fine.

% X -multiwindow

// ...snipped

(II) xorg.conf is not supported
(II) See http://x.cygwin.com/docs/faq/cygwin-x-faq.html for more information
LoadPreferences: /home/aaronfi/.XWinrc not found
LoadPreferences: Loading /etc/X11/system.XWinrc
LoadPreferences: Done parsing the configuration file...
winDetectSupportedEngines - DirectDraw installed, allowing ShadowDD
winDetectSupportedEngines - Windows NT, allowing PrimaryDD
winDetectSupportedEngines - DirectDraw4 installed, allowing ShadowDDNL
winDetectSupportedEngines - Returning, supported engines 0000001f
winSetEngine - Multi Window or Rootless => ShadowGDI
winScreenInit - Using Windows display depth of 32 bits per pixel
winAllocateFBShadowGDI - Creating DIB with width: 4560 height: 1920 depth: 32
winFinishScreenInitFB - Masks: 00ff0000 0000ff00 000000ff
winInitVisualsShadowGDI - Masks 00ff0000 0000ff00 000000ff BPRGB 8 d 24 bpp 32
winInitMultiWindowWM - Calling pthread_mutex_lock ()
winMultiWindowXMsgProc - Calling pthread_mutex_lock ()
MIT-SHM extension disabled due to lack of kernel support
XFree86-Bigfont extension local-client optimization disabled due to lack of shared memory support in the kernel
Fatal signal received in thread 0x80000038
(EE) Segmentation fault at address 0x12c
(EE) Attempting backtrace on pid 9892
(EE)
==================== GDB Backtrace ============

GNU gdb (GDB) 7.5.50.20130309-cvs (cygwin-special)
This GDB was configured as "i686-cygwin".

==================== Backtrace ================

Thread 10 (Thread 6552.0x64c):
#0  0x778e000d in ntdll!DbgBrea(EE) kPoint ()
   from /cygdrive/c/Windows/SysWOW64/ntdll.dll
No symbol table info available.
#1  0x7796f99e in ntdll!DbgUiRemoteBreakin ()
   from /cygdrive/c/Windows/SysWOW64/ntdll.dll
No symbol table info available.
#2  0x71f348ed in ?? ()
No symbol table i(EE) nfo available.
#3  0x00000000 in ?? ()
No symbol table info available.

// snipped...