joluveba I downloaded the second one, 2.2 Beta. It comes with KDE Plasma.
There were a few non-obvious hoops to jump through, but all my guesses turned out to be correct, and I got Pisi running with Plasma in a new VM. The toughest hoop was discovering that the YALI installer is listed in "Favorites," and I needed to find that and run it. There's no icon or link saying "Install" as there is in other live ISOs I've used.
Once I figured that out, it was easy from there. The installer is very straight-forward, and seemed very much like Solus' installer. Hmmm ... I'll bet they're related, or both are descendants of the same ancestor installer. 😁
In order to install VirtualBox's Linux Guest Additions, I needed to run Dolphin as root from the terminal. And if anyone else needs to do that, be aware that the application name is simply "dolphin".
Now I can use it full-screen, and get on with some serious configuration. This has been a very pleasant adventure so far.