AFAIK tapx-templating will not work with the normal tapestry web jars on the classpath and must be a separate app.
I have written a class which can render components offline within a tapestry webapp for tapestry-cometd. The code can be found here https://github.com/uklance/tapestry-cometd/blob/master/src/main/java/org/lazan/t5/cometd/services/internal/ComponentJSONRendererImpl.java Note: It's a bit of a hack!
