Hi. Thank you for this.
None of us have much Windows experience.When AT&T was supporting the project, a developer was building the stable releases and packaging them manually. We were already having some problems with the installer occasionally wiping out someone’s PATH so I think we disabled that feature in the install maker. So around 2014 we lost all that. A while later, Erwin Janssen set up the CI build on Appveyor. There were a lot of messages on GitHub about this including using cmake for 64 bit builds.
Chiel ten Brinke also commented a lot on this in 2017. See for example https://github.com/ellson/MOTHBALLED-graphviz/issues/1218#issuecomment-291091327
I believe we just pointed to the Appveyor build and hoped for the best. I don’t think anyone sorted out any installer other than the zip file created on Appveyor.
Around this time we were all really distracted by major life issues and probably not responding enough or we considered the job basically done because the builds ran on Appveyor. Possibly this led to disappointment on the part of Erwin and Chiel etc. or maybe they just figured they had brought it as far as they needed to and stopped working on it. It’s history at this point.
I don’t even remember how Travis got into the picture here. Possibly it started around here: https://github.com/ellson/MOTHBALLED-graphviz/pull/55
One take-away is that it takes a lot of care+feeding to maintain an active open source project including builds and releases. I am not sure how to make that happen without it being anyone’s day job.