I now have a nice solution that uses videopad to reduced large 4K videos to smaller HD during the editing process. This keeps video pad from buffering large 4K videos and not getting any work done. Here's how the solution works.
The drone videos that I have only produce one video stream with no audio. However, the video pad likes to have a 2 streams with video and audio. So the solution is to read all the MP4 files into the computer and automatically write 4K video files back with two streams using video pad. It also loads all the files again and writes them to a different directory using 1920x1080 resolution (HD).
Then the operator renames this smaller directory to the working directory so that all editing of the video pad files operate on this generic directory name. That way, all buffering is done with the smaller resolution files and video pad is very fast. Then for the final rendering process after all editing is completed the high resolution directory is rename to the working directory and the operation is run one final time with 4K video.
Here is last year's video September 2021. I did all manually last year and now have I have a nice procedure.
https://www.youtube.com/watch?v=ssVow_wpWRU
Here is a link to the processing files. I use TCC_RT which the superset of CMD and free to download. The development version is like $100.
https://1drv.ms/u/s!AuSetTxgq7JxqYgXcNNpmfvV3OnJ_A?e=YSDZd6
This uses v11.73 of video pad.