To Owlie:
Thanks for your thoughts; hoping it's not that I've bought the wrong shoes but always a possibility ...

To Trista:
Hoping your idea will be the quick solution to the numbness - thanks. Never thought of the cleats since I'm new to such things, so it's well worth a try to see if that's what's causing the numbness. (The LBS put the cleats on the shoes so I just expected they got it right).

Thanks so much; any other suggestions still welcome; especially interested to see what people think about the space I have in the top of the shoe