Animating a garbage matte

Hi there,
So far I've had crash problems with Mocha Pro ofx, and I realize that I've been using Mocha (ofx and standalone) so often these 2 past years that I can't even make a choice about what I may use instead...
I just want to animate garbage mattes which cover unwanted objects on a green screen key, the main job is already done inside a Primatte 5 node (just the garbage matte operation lacks).
Therefore, given that the operation will occur on 40 clips in this project, I prefer asking about best practices.
Up to now, lost and scared in the Mocha-less jungle, I've tried stuffs and questions popped-up :
- Fu tracker : works ok, but how to connect it to Primatte 5 garbage matte input, or how to connect a polygon or spline to the tracker results and also to the garbage matte input of Primatte ?
- I've manually keyframed the polygon mask (pfff, am I in 2017 ?) to be sure I'll get at least one clip to export... Ok, why not so far, but how does the automatic keyframing work please ? Because I manually right clicked the center parameter of the polygon to choose "set key", but that's not bearable more than half an hour
- Anyone using Mocha Pro 5 ofx in Fusion around ?
Any comment highly appreciated, thx in advance
So far I've had crash problems with Mocha Pro ofx, and I realize that I've been using Mocha (ofx and standalone) so often these 2 past years that I can't even make a choice about what I may use instead...

I just want to animate garbage mattes which cover unwanted objects on a green screen key, the main job is already done inside a Primatte 5 node (just the garbage matte operation lacks).
Therefore, given that the operation will occur on 40 clips in this project, I prefer asking about best practices.
Up to now, lost and scared in the Mocha-less jungle, I've tried stuffs and questions popped-up :
- Fu tracker : works ok, but how to connect it to Primatte 5 garbage matte input, or how to connect a polygon or spline to the tracker results and also to the garbage matte input of Primatte ?
- I've manually keyframed the polygon mask (pfff, am I in 2017 ?) to be sure I'll get at least one clip to export... Ok, why not so far, but how does the automatic keyframing work please ? Because I manually right clicked the center parameter of the polygon to choose "set key", but that's not bearable more than half an hour

- Anyone using Mocha Pro 5 ofx in Fusion around ?
Any comment highly appreciated, thx in advance