Hi George, All, Some progress: The MacPorts folks fixed the problem with PDL so that a 'port selfupdate' will then allow PDL to build and then install. With that, Demeter then installs, though there are some warnings about missing dependencies (Heap, XMLRPC::Lite, File::Slurp::Tiny, Encoding::FixLatin::XS) which I'm guessing are relatively new dependencies, not included in the Portfile. I installed these missing perl modules using the 'perl -MCPAN -e shell' The basic Athena and Hephaestus and Artemis run OK, though I haven't done exhaustive testing. I did have to change the default gnuplot terminal from Qt to wxt for each of Athena and Artemis (I did not try plotting with Hephaestus). The settings page for Artemis is not easy to find -- it might be that the multiple-small-screen layout is difficult to map to the Mac window styling. As for Xorg vs XQuartz: The correct answer should be "neither". Neither Demeter nor gnuplot actually use X11 at all -- both are using wxWidgets, which does not use X11 on Mac. Similarly, I cannot understand the dependency on all of llvm, gcc4.9, and gcc5.2 from MacPorts. Most of the code even for MacPorts appears to be built with the *system* (ie, Apple-supplied) clang compiler. I can believe it "necessary" (well, really, "easiest") to build all of gcc to get gfortran, but not twice. And, yeah, if you have to install from source, it sort of matters. I do not know where to update the MacPorts Portfile. All links to the actual portfile scripts seem broken to me, but maybe they're available someplace. --Matt