Sure. Follow instructions and send us IP addresses of all needed back-end servers. You no need to specify which of them for production or test purpose.
You should not!
Actions API work with sha256 digest and don't expect a raw mobile phone from online lender. We just check if there is same digest in our database and send you leads data.
It depends on traffic volume, and season. So it's better to consult with our representatives. Take a look into Contacts section of main site and feel free to ask questions via email or chat.