STR..
1. On a TB39 Windows build of master, open the Page Styles Dialog to the Page tab (F11 -> Page Styles -> Default: Modify context, or Sidebar Properties -> Page panel: Size -> More button )
2. In the Paper format section make a change (size dropdown, or orientation radio buttons)
3. Select the Columns tab of the Page dialog
4. LO crashes with Windows C++ Assertion failed error

If Columns are adjusted first, there is no crash when changing page size or orientation.  Issue does not manifest on current 4.3.2.2 release
build ID: edfb5295ba211bd31ad47d0bad0118690f76407d

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On Windows 7 sp1, 64-bit en-US TB 39 debug build
Version: 4.4.0.0.alpha0+
Build ID: 9177329a425cf70b515d1f266132838894fe54c6
TinderBox: Win-x86@39, Branch:master, Time: 2014-10-06_01:02:02

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-- Error Dialog-- 
Microsoft Visual C++ Runtime Library
Assertion failed!
Program:C:\LODev440_20141006_TB39\program\vcllo.dll
File:C:\cygwin\home\tinderbox\master\include\rtl/ustring.hxx
Line:421

Expression: index >= 0 && static_cas<sal_uInt32>(index)<
static_cast<sal_uInt32>(getLength())

For information on how your program can cause an assertion
failure, see the Visual C++ documentation on asserts

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Stack trace (Process Explorer)

wow64cpu.dll!TurboDispatchJumpAddressEnd+0x6c0
wow64cpu.dll!TurboDispatchJumpAddressEnd+0x676
wow64.dll!Wow64SystemServiceEx+0x1ce
wow64.dll!Wow64LdrpInitialize+0x42a
ntdll.dll!RtlUniform+0x6e6
ntdll.dll!RtlCreateTagHeap+0xa7
ntdll.dll!LdrInitializeThunk+0xe
USER32.dll!WaitMessage+0x15
USER32.dll!DialogBoxIndirectParamAorW+0x108
USER32.dll!SoftModalMessageBox+0x757
USER32.dll!SoftModalMessageBox+0xa33
USER32.dll!MessageBoxTimeoutW+0x52
USER32.dll!MessageBoxExW+0x1b
USER32.dll!MessageBoxW+0x18
MSVCR110.dll!raise+0x3eb
MSVCR110.dll!_wassert+0x490
vcllo.dll!?settingOptimalLayoutSize@Dialog@@MAEXPAVVclBox@@@Z+0x44f
vcllo.dll!?ImplFindMnemonic@MnemonicGenerator@@IAEGABVOUString@rtl@@@Z+0x36
vcllo.dll!?RegisterMnemonic@MnemonicGenerator@@QAEXABVOUString@rtl@@@Z+0xc2
vcllo.dll!?ImplStartExecuteModal@Dialog@@AAE_NXZ+0x394
vcllo.dll!?StateChanged@TabPage@@UAEXG@Z+0x43
vcllo.dll!?ImplCallInitShow@Window@vcl@@AAEXXZ+0x5d
vcllo.dll!?Show@Window@vcl@@QAEX_NG@Z+0x625
vcllo.dll!?ImplChangeTabPage@TabControl@@AAEXGG@Z+0x472
vcllo.dll!?SetCurPageId@TabControl@@QAEXG@Z+0x147
vcllo.dll!?SelectTabPage@TabControl@@QAEXG@Z+0xa9
vcllo.dll!?MouseButtonDown@TabControl@@UAEXABVMouseEvent@@@Z+0x6a
vcllo.dll!?ImplAsyncFocusHdl@Window@vcl@@QAEJPAX@Z+0x3244
vcllo.dll!?ImplAsyncFocusHdl@Window@vcl@@QAEJPAX@Z+0x417b
vcllo.dll!?ImplAsyncFocusHdl@Window@vcl@@QAEJPAX@Z+0x4f29
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x53d6e
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x58282
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x5bdb9
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x5cb91
USER32.dll!gapfnScSendMessage+0x332
USER32.dll!GetThreadDesktop+0xd7
USER32.dll!CharPrevW+0x138
USER32.dll!DispatchMessageW+0xf
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x15b76
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x15cc2
vcllo.dll!?OpenTTFontBuffer@vcl@@YAHPBXKKPAPAU_TrueTypeFont@1@@Z+0x1666e
vcllo.dll!?ImplCallEventListeners@Application@@SAXPAVVclSimpleEvent@@@Z+0x1de
vcllo.dll!?Yield@Application@@SAXXZ+0xc
vcllo.dll!?Execute@Dialog@@UAEFXZ+0x8b
ntdll.dll!RtlAllocateHeap+0xac
ntdll.dll!RtlInitUnicodeString+0x164
ntdll.dll!RtlAllocateHeap+0xac
sal3.dll!rtl_cache_alloc+0x109
sal3.dll!rtl_cache_free+0xb0c
sal3.dll!rtl_string_newFromLiteral+0x63