@Wishbringer
I must admit that I have never tried to use AVStoDVD as BD "downgrader"... mainly because I do not have any BDs...
But, if you can provide a short sample of your BD or, at least, the AVStoDVD project log file, it could be a good start.
Gizzin's method (
) should work well, even if it is not a "one-click" solution.
Bye