yes I downloaded the EZKeys App and the MIDI files I bought.
EZKeys is now working with the MIDI files.
The installation menu did not offer a Change Location option and it looks like Toontracks installed, by default,the MIDI files in:-
Mac HD/ Library/ Application support/ EZKeys /EZK-GRANDPIANO
I like to organise my Hard Drive so that all my samples for various Samplers are in the same place, so I guess I can move this sub folder and reset the EZKeys App to load from there.