Important to note: this is an unofficial build of LineageOS, i.e. a custom rom. I use LineageOS on my devices for the support regular updates officially support

Important to note: this is an unofficial build of LineageOS, i.e. a custom rom. I use LineageOS on my devices for the support regular updates officially supported devices get, which you don't with this one. That said, why would you need to flash Google Apps on it? In order to cast?