Licensing.

How does the SQL Backup Pro licensing works?

I know there are 2 pieces - client and server to the SQL Backup Pro.
1) Is the license just for the client?
2) Are there limitations to number of sql server instances? Or is this a question for our contract? I think we have the SQL Toolbelt http://www.red-gate.com/products/sql-development/sql-toolbelt/

Thanks!