Apparently I can’t include links in my post, so we get to step through the full website. Go to the Stormcoast Fortress website (use Google… no links allowed for me!), and on the left-hand nav bar under the “ScmDraft 2” section, click “Download”. Click on the first link on the page (“Newest alpha builds”). Scroll down just past the screenshots and download version 2019.07.09(W) – it’s just under the Donate button. Just open the .zip and copy all the files to a folder on your desktop and launch the “ScmDraft 2” file.
Note that I could not start the editor while SC:R was running – I was getting a “Cannot read data” error. Close SC:R and then launch the Default profile.