I must comment on your RaceRender working fine on Win7. My hobby is RadioConrtolled airplanes and I wanted to have GPS overlay on my video.
Editing in good quality H.264+HAVC means choosing format settings and software for the project.
My choice was GoPro Studio (free but not supported anymore) and GoPro7 settings for acceptable file size:
1080p, 1920x1080, 25 or 50 Fps, PAL. On a 64Gb card I get 4.5 hours of recording.

This is a footage (sorry for Icelandic language):
https://www.youtube.com/watch?v=CXqQP-pdRng

Just sharing this information and praising RaceRender for their fine product at reasonable price!