installing plugins in

why is it not possible to install a wpmudev plugin like hummingbird directly out of the wordpress installation of while it is possible to do so with! for it was a one-click install in the wordpress backend using wpmudev dashboard. for you click on hummingbird install, it opens a new tab which directs me to where i again click "install", and then nothing happens. the only possibility i have is to manually download it and install it like any other premium plugin via the wordpress upload plugin feature.... thanks