You may distribute the generated code in binary form and associated Liquid Runtime as part of your product to your end users royalty free, provided your product adds significant primary functionality to the library (i.e. you can't just distribute the library).
Any person who needs to generate source code or access the generated source code and associated Liquid API (typically a back end or middle tier developer) needs to have an XML Data Binder (or Developer Bundle) license.
Any person who needs to access the API of the generated code in binary form (e.g. .dll) and associated Liquid API (typically a front end developer) needs to have a runtime license. A runtime license is included with the Data Designer Edition, XML Data Binder and Developer Bundle.
Depending on how many developers you have, and how your team is structured, it may be advantageous to purchase Concurrent licenses instead of node locked licenses, as 1 concurrent license covers up to 10 developers and is significantly less expensive.
Please let me know if you require further clarification.