Hey there,
If your getting the message: "You must have permission to add apps to at least one Facebook Page to perform the requested action," try creating a page for your store within your new Facebook profile. You can do this by going to the top right hand corner of the page, pressing the downward arrow button and then selecting "Create page." Once you've created a page for your store, you should be prompted to select the store when using the app in the future.
Hope this of some assistance,
Matt