What happens when you view the network traffic in the chrome developer tools? Can you see the values as request parameters?
Are the select element ids (in the html) what you think they are? There's an issue where the clientId is ignored by tapestry for select. And tapestry adds a unique suffix to the end of the id. This has been fixed in recent 5.4 builds but probably not on 5.3. You might need to add a data- attribute to the select element and bind to that (using an appropriate selector) instead of the unpredictable id.
