Community search results (and other server controls, such as CommunityGroupBrowser) use the TemplateGroupProfile and TemplateUserProfile properties to form quicklinks. In Release 7.6.6, these properties expected the templates to be relative to the currentfolder. But, in later versions, these properties changed, so that the url was required to be relative to the site root.
Update your sample template so that the path begins with the site root folder. Ektron does not update templates on the site.
For example, a template previously identified as TemplateGroupProfile="CommunityGroups.aspx" needs to be changed to TemplateGroupProfile="developer/Community/CommunityGroups.aspx" (assuming that developer is your site root folder.)
<%= heading %>