Hello. Great plugin!
I've noticed that any addresses with a pound or hash (#) character do not get latitude and longitude values back.
I've tried to troubleshoot this myself in the store_locator.php
I modified the $newaddress variable to look like this:
$newaddress = urlencode($address);
But that didn't seem to change anything. I tried sending the resulting URL to maps.google.com/maps/.... when the value is URL-encoded, and Google sends back a JSON object like it should.
With this running behind-the-scenes as a hook to "save_post", I'm not really sure how to further debug it.
Any idea? And you're welcome to use the urlencode() in a future update if you think it is valuable.