It's just too old, too janky. It crashes, the day/night system where you can't pass time or rest, your companions just randomly leave and go back to base where you then can't get them to go with you again, etc. Too many problems, but then also to release an update as a paid new version is infuriating. I liked the game enough that I'd have considered SoD2 or SoD3, but probably not with this kind of shady dev BS.

Iz Gud

You can't buy this version anymore, but the basic content is the same as the newer version. The base game and Breakdown are great, they're very fun open world zombie games with rogue elements. Lifeline, on the other hand, is a waste of time and not really worth playing.