HRESULT XPackageUninstallChunks(  
         const char* packageIdentifier,  
         uint32_t selectorCount,  
         XPackageChunkSelector* selectors  
)  

HRESULT UninstallBigMaps()
{
    char id[XPACKAGE_IDENTIFIER_MAX_LENGTH];
    HRESULT hr = XPackageGetCurrentProcessPackageIdentifier(_countof(id), id);
    if (FAILED(hr)) return hr;

    XPackageChunkSelector selector;
    selector.type = XPackageChunkSelectorType::Tag;
    selector.tag = "BigMaps";

    hr = XPackageUninstallChunks(id, 1, &selector);
    return hr;
}