xenporta (portal) 1.5.6

Hello, i am using XenPorta (Portal) 1.5.6 And when i go to XenPorta tab on the edit bar thing i click portal and this pops up https://gyazo.com/61e5fb786ab93cfa67ab59e75e2cd49d But say i try to drag one of the blocks over nothing works anyone know why?