Web Part Connection Issues I was having some trouble configuring Web Part connections between multiple web parts on a single page. The following article was able to assist, as there are a number of custom (third party) Web Parts on the page that being used in the connections to collect and pass parameters or filter values to Web Parts.
The issue occurred if the page was saved using SharePoint Designer. When the page is saved using SharePoint Designer after configuring a Web Part Connection, all Web Parts with previously configured connections disappear off the page. when in design mode, the Web Parts are still on the page, but are not visible when viewing the shared view of the page.
See
Web Part Connection Issues for details.