i been messing about with getting some Lower 3rds graphics with an alpha layer working on casper CG, and have arrived at the solution that the only way i can make video clips on a windows computer with alpha channel (without using adobe) is to use the DNxHR codec in Davinci resolve,
however i can not get casparCG to play the DNxHR codec.
I haven’t had any luck playing back DNxHD/HR with integrated alpha. I usually use DNxHD/HR without Alpha and a separate alpha file with _A. Codecs that work with integrated alpha in Caspar are also Animation and ProRes4444 but they need much more performance than DNx.