My son has been diligently working his way through the book and loving it.
He just tried to compile the source code he downloaded from your site for the LavaVision plugin (around page 85) and he gets an error saying:
src\lavavision\LavaVision.java:37: error: no suitable constructor found for BlockIterator(LineTracer,boolean)
I looked into the CanaryMod API documentation and it looks like BlockIterator in that case no longer has a boolean for whether it includes air blocks or not.
When I removed that argument in the sample code, it compiled, although I haven’t confirmed whether the plugin now does what is expected.
Perhaps something that needs to be updated for the latest changes to CanaryMod?