In the wall chart viewer it's only using the thumbnail. But, when you print it should use the image stored on the computer. Best to save it as a file or print to PDF before you can judge the image quality.
Thank you for your response post. On looking into your proposed methodology and comments, I found that when running RM on Mac, there is no capability to print to PDF. And in general, saving a Wall Chart before printing does not cause the thumbnail images to be swapped for higher, full-sized image files. Now because I tried saving my Wall Chart to each available file type (i.e. *.emf, *.bmp, *.jpg, *.pcx, *.png, and *.tga), what I did find was that there is only way to get high resolution images on the Wall Chart. That was accomplished when I saved the Chart as an *.emf, then opened it on the Windows10 side of my Mac in their MSPaint app, where I then resaved the Chart as a *.jpg. (unfortunately, going straight to *.jpg only resulted in my be left with low quality thumbnail images as putput). In conclusion, while I now have a means to the end I sought to achieve, I doubt there are many Mac users running RM that also run Windows10 via a Parallels virtual machine. I suggest, given that genealogy is all about sharing your information with others, RM for Mac really needs to upgraded so that all reports produce high-quality / no-pixelation images in just one straight forward step.