I believe the account is limited to one computer only. It doesn't matter how many numbers you have attached to the account. On the other hand, try and install the application on both computers and login using your details. If it works then there is no additional configuration needed. Place calls from both computer and assign those numbers to each computer. It is most likely possible that you will be able to use it even if it is the same account. If you encounter errors then the account can be used on a single computer only.