No. In general, stick a break point on the encodeBegin/encodeEnd methods of the component renderer - then you can see where it all goes wrong.
It can also be useful to create a JSF phase listener and look what JSF phases are being traversed.
You may not even be getting to the render phase!
I am new to JSF and SEAM. What do you mean by create a phase listener. Is this a class I need to write, or is this done via a configuration setting? Any link to documentation would be appreciated.