Using Camera Raw as an editor with Photomechanic

On my existing MacBook, I have Photoshop set up as my default editor within Photomechanic. So, when I open an image it opens Camera Raw for me to perform the edit. This is great and just what I want. On my new Laptop, I set up Photoshop as my editor but it is the full Photoshop screen that opens up rather than Camera Raw. I have tried everything and can't work out where the setting is to enable Camera Raw to open when trying to edit an image. Anyone got any ideas ?