While not a bug, for those who have not purchased Game Dev but are considering it, you need to allow the app to phone home at least once every six months or it will deactivate. 

SMS changed the system requirements page between yesterday and today but are trying to claim it was there when the product went live in August of last year. 

Just a heads up for those who might not be aware of this.  There's more over at the "official" forum at RDNA.