I'm not sure what your issue is. Are you having trouble setting up the store on your remote server site or are you having trouble setting it up locally?
"As a test I setup a PowerStore2oo test site on my local server (MAMP Pro) and set it up as a standalone site ( all files at root and not in a sub-directory) with no problem."
So you are able to get the site working locally? If that's the case, you will need to get the root url for your remote server and set this variable to it:
If that's not what your situation is, could you please clarify?