Hi, sorry to hear you are having trouble. Although the hide option has been tested with the latest free version, it might well be that in combination with your theme (or another plugin) and the recent changes in 1.7 and 1.8, a conflict has emerged.
It would be very helpful to see it live on your site. So if there is a possibility to recreate the popup but this time only on one test page (so not adding it as a widget but straight into the page Text tab) then I can take a look and see what is going wrong.
Otherwise, please tell me what theme and possibly conflicting plugins (sliders, gallery plugins etc.) you are using so I can try recreating the issue ๐