You just need to add the overlayClose SimpleModal option. You can do this by opening smcf/js/smcf.js and changing:
$('.smcf_link, .smcf-link').click(function (e) { // added .smcf_link for previous version
e.preventDefault();
// display the contact form
$('#smcf-content').modal({
closeHTML: "<a href='#' title='Close' class='modalCloseX simplemodal-close'>x</a>",
position: ["15%",],
overlayId: 'smcf-overlay',
containerId: 'smcf-container',
onOpen: contact.open,
onShow: contact.show,
onClose: contact.close,
zIndex: 10000
});
});
To:
$('.smcf_link, .smcf-link').click(function (e) { // added .smcf_link for previous version
e.preventDefault();
// display the contact form
$('#smcf-content').modal({
closeHTML: "<a href='#' title='Close' class='modalCloseX simplemodal-close'>x</a>",
position: ["15%",],
overlayId: 'smcf-overlay',
containerId: 'smcf-container',
onOpen: contact.open,
onShow: contact.show,
onClose: contact.close,
overlayClose: true,
zIndex: 10000
});
});
Hope that helps.