I was not aware that the Highslide JS files have ever been available on a CDN. AFAIK, Highslide JS has always been a "download the files and host them yourself" application. Are you using some sort of third-party plugin, like the one for Joomla? If so, you need to contact the folks who provide the plugin.
I am using HighSlide to open HighChart in big popup window when we click on chart. Those CDNs were working until last week or so. As we are still evaluating HighCharts/HighSlide and don't have license yet, can't download HighSlide locally. I guess we need to have license to download HighSlide plug-in.
No, you don't need a license to download Highslide JS. In fact, there's no system of license keys in it at all - it's completely open source. Grab the zip package here: http://highslide.com/download.php. Don't bother with any of the subsets of the script - use only highslide-full.js or highslide-full.min.js
I have no idea how that works with Highcharts, which I've never laid eyes on.
I think we need to buy license for non-profit organizations. This is what I see in their website.
Highslide JS is dual licensed.
If you want to use Highslide for a personal website, a school site, your family's photo album or a non-profit organisation, you don't need the author's permission, just go on and use Highslide.
If however you want to license Highslide JS to use on a commercial or governmental website, web application or SaaS project, you need to purchase a commercial license.
Yes, you need to purchase a license, but you can download the software whether you have a license or not, and the software doesn't change if you have a license. There are no license keys, no serial numbers, no "locked" features.
Frankly, I'm not sure I would purchase a license for anything short of a fairly profitable commercial enterprise. Highslide JS is virtually "abandonware." There is no development going on, and as far as I can tell, there is no support being provided whatsoever. Collecting license fees under those circumstances strikes me as being a bit brazen.