I have been working with post processing code that Didier sent me and have some difficulty with it. The "fun = quant" does not seem to be working. I noticed in your RMD, you spelled "QUANT" (all caps), but the documentation specifies, "quant" (all lower case). I changed it to lowercase, and it does seem to recognize it, but does not produce an image (NOTE, I am using ver 13.0.1). The same is true for the PDF (attached).
Any suggestions?