Hmmm is just that you mentioned that the first time you downloaded it, nothing happened, and only after downloading again you ran into issues. But the game hasn’t been updated since last year, Itch.io shows “last updated” on the game page, and there’s been no changes since then. So both times you downloaded, it was the exact same version.
Also… from my understanding, malware doesn’t work based on how long you leave a game running… Leaving a normal game running for hours doesn’t allow someone to “get in” to your PC. For something like that to happen, the game itself would need to have a backdoor or remote access program built in.
I know it’s stressful and maybe you don’t mean any harm, but unfortunately it’s a big claim to suggest malware is in the game without solid evidence, it could really hurt the developer because ur basically insinuating they put it in the game :c.. also ive seen quite a few youtubers playing the game without any trouble. But any who, this is just my two cents, I hope everything is well with you! ^^