According to the debug output encoding is running fine, it's just slow:
x264 output: 462 frames: 0.47 fps, 4912.65 kb/s
QTGMC Placebo and restore with speed -25 seems is a slow combination.
-> don't see a problem here aside from you using too slow settings for your taste.
Cu Selur
x264 output: 462 frames: 0.47 fps, 4912.65 kb/s
QTGMC(Preset="Placebo", InputType=0, TR2=3, Sharpness=0.4, SourceMatch=3, Lossless=2, ediThreads=2)
srestore(frate=30.000,omode=6,speed=-25)
-> don't see a problem here aside from you using too slow settings for your taste.

Cu Selur
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Dev versions are in the 'experimental'-folder of my GoogleDrive, which is linked on the download page.
Dev versions are in the 'experimental'-folder of my GoogleDrive, which is linked on the download page.