Unfortunately, we have no update of “Rendering with Radiance” since the first edition, since it wasn’t a big money-maker. Glad you like it in any case, as the authors put in a lot of effort putting it together!
Your corrections and updates are appreciated, and there are many more. Since it’s publication, we’ve added many new features, including the ability to run annual daylight simulations and bidirection scattering distribution functions (BSDFs). Most recently, we added the ability to do hyperspectral calculations. A second edition would be quitea bit larger than the first.
The winxmit.cal file does still exist. It should be installed with the rest of Radiance, and will be found if your $RAYPATH environment variable is set correctly. If you are missing this (and other) library files, you can always download the “Auxiliary files” overlay from radiance-online.org under “Download/Install”.
Cheers,
-Greg
P.S. There is a downloadable PDF of “Rendering with Radiance” with a few minor updates and corrections, which you may download for $7 US from Randolph Fritz’s site here.