As I understand... the limit applies to the download of the installer and not the activation itself. Keep the installer (the 20mb file) and that's it. Correct me if I'm wrong! and I will delete the post to avoid confusion.
It's a known problem for us with AMD and no HDR, not IXEG. I believe it's a sort of z fighting problem. Not only aircraft gauges have this problem, also terrain, ground objects, etc. Saldy HDR takes some frames in my system so I try to use analog gauges.