Just to add. A bit of Loctite Threadlocker Blue 242 (temporary/removable) on the screw will just lock everything down tight. Just hand tighten with the provided allen wrench.
When test fitting, there's a bit of slop or gap with the adapter, so the plate rotates/wiggles a bit. With the threadlocker, no movement at all. 
So with minimal investment you extended the use of your Manfrotto QR plate and can start to use Arca-Swiss plates too on one ballhead. 

