The real answer is I'm just making a single package for a project on my development machine. I have a 1-click build for executables and test-stand deployment so I can press run and walk away, but without a separate build computer there isn't really a significant enough need to buy the API -- it saves a few clicks. However, that does look to be the difference, either pro edition was always required or it is now, but when I turned on evaluation mode it worked.
I stumbled across this post from a few years back: https://forums.jki.net/topic/2466-is-there-a-way-to-create-a-vi-package-in-vipm-using-command-line/ I've confirmed I have the format right and can at least open a specific package using the command line ("/command:vipm_open_build"), but the "build" command does nothing.. Is there still a command line build feature for VIPM 2017? Thanks