With _ATL_NO_MSIMG defined, there is no function CDCT::GradientFillRect (atlgdi.h). CSplitterImpl::DrawSplitterBar (atlsplit.h) calls this function and checks only for _WIN32_WCE, not for _ATL_NO_MSIMG. Affected Versions are 8.1.11324+.
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Fixed by checking for _ATL_NO_MSIMG. SPLIT_GRADIENTBAR has no effect if _ATL_NO_MSIMG is defined.