While I have not played a full campaign or anything, I have completed several scenarios without any problems. It is not slow or glitchy. I installed it via Steam, on Mac Catalina. There was no need for a manual install, unless I'm misunderstanding what a manual install means. It installed directly from the CrossOver interface.
I am not sure how the metadata gets updated, but the catalog entry is incorrect. This game is supported, by a live company, Killerfish Games. They are a small studio but they give (limited) support, including via the Steam forum for this game.