We’ve been discussing the CatalogURL a couple of times already, but people seem to have no idea how they should install, say macOS Sierra 10.12.3 from it.
Long story short; you can now find an example in one of my github repositories (HandyScripts).
You can use my script and change it for any of the packages that you would like to install (from the command line). There are three variables (key, url and packages) that you should keep in line with what the used sucatalog.gz is telling you to use. That’s it. Ok. You may want to change the language (distribution) but that’s about it.
Edit: You can cd to /tmp and edit the downloaded .dist file and run:
productbuild --distribution 031-91606.English.dist --package-path 031-91606 installer.pkg
This should create a working installer PKG.
Have fun 😉