I'll make this short and sweet: Giocoso does not run on openSUSE Leap.
The reason for this is that Giocoso Version 2 requires the Bash shell version 5 and up, and openSUSE -being based on the SUSE Linux Enterprise Server and thus prone to being quite conservative in its choice of software- only includes the Bash shell version 4. That is not modern enough (though version 5 was released back at the start of 2019, so I would have hoped SUSE and thus openSUSE might have gotten themselves a bit more modern by now!). Launching Giocoso on openSUSE Leap (tested on 15.3 and 15.4) thus produces only this error message:
That is a new result for Giocoso Version 2, I'm afraid, because the code now uses more Bash version 5-specific features. Thus, where Giocoso 1 ran on openSUSE Leap+Bash version 4 just fine, Giocoso 2 cannot do so.
I have searched high and low for instructions on how to retrofit Bash version 5 onto this distro, but have turned up nothing. Trying to install a suitable version 5 rpm by hand only produces dependency hell, so I wasn't prepared to go that route. If you do know how to do it, then Giocoso Version 2 will run perfectly fine on the resulting operating system... though, technically, it won't really be openSUSE Leap at that point, I suppose!
Giocoso Verssion 2 does, however, run successfully on GeckoLinux (the rolling version) and openSUSE Tumbleweed. Gecko is based off Tumbleweed, and Tumbleweed is a 'rolling distro', meaning that although it's based on SUSE Enterprise Linux, it's kept way more up-to-date (or bleeding edge, depending on one's point of view!) Both therefore ship with Bash version 5 and therefore neither has any difficulty running Giocoso.
I will, of course, keep the matter under review, and should openSUSE Leap ever increment its Bash version (or instructions on how to do so become widely available), I'll definitely do what it takes to get Giocoso running on it. But for now... use a different flavour of SUSE (or another distro entirely!)