We are using Gmap API Key in our application.

We have web based mobile application for delivery of medication at pharmacy store. In this application we use Gmap, to display direction/path between pharmacy store. 

1. It show Sample Period 28 Days, does it mean we have to generate another API Key after 28 days. If "Yes" then can you please guide us to get solution regarding it.
2. API Key which I have generated if for "Allow All Referrer", do u restrict the use of API Key at domain name level.
3. How many direction request can be generated in Courtesy limit and what if its exceeded..
4. Can we generate new API Key, after previous API Key is expired.