When the Ribbons block webpart picker...

On customized SharePoint pages, particularly Search Center pages, very often you end up with something like this when trying to add web parts to the page:

Notice that some of the webparts and categories are blocked by the Ribbon. If the one you want is blocked, first add any one that's clickable, then click on Edit Web Part in the newly added webpart, once the Edit Panel shows up, click on the Add a Web Part link again, now the webpart picker control shows below both the Ribbon bar and the header bar:

Nothing is being blocked anymore. Add the webpart(s) you desire, and delete the very first one that you added in previous step if it's not needed.