1)How to change the image and the text share in the Facebook invite?
Go to /themes/wowonder/layout/container.phtml >>And paste your code in head tag
<meta property="og:image" content="http://www.sitename.com//themes/wowonder/img/og-image.jpg" />
Upload your own website banner as “og-image.jpg”You can also use og:description’ meta tag,If defalut meta tag support offer by wowonder is not working properly
then oepn this linkhttps://developers.facebook.com/tools/debug/og/object/
Put your website url and allow facebook to fetch new meta tag info for your website.