Here is a link to sample files for the problem
https://1drv.ms/u/s!AgEkZSUlkAcxgb0eg2M8ATSCee6zgQ?e=ieBwME
1. Shot match used to work in the previous version of Movie Edit Pro but not in version 21.0.2.130 (UDP3). I have given you a set of pictures showing you how I tried to match one frame. Either it came out almost black or almost totally white. The movie is black and white. There are sample files to test it out.
2. I am using a larger than standard input frame size of 740x500. The reason is that I am correcting jitter so to do this the oiginal frame 720x480 has been enlarged with the edge colors bled to the edge of the new frame. This allows adjustment without creating jittering black bars on the edges. The movie has been set to be also 740x500 with aspect ratio of 4:3. When I output a section of the movie to use an external jitter reduction program and then bring back the result, the framing is grossly off, letterboxed. So I got to adjust the size to the Original Size which corrects this problem. The input file is alwasy Lagarith which lacks aspect ratio information, so if the input file has the same size as the target movie, the frames should match perfectly. There is a picture of what it looks like on input. Using an external jitter reduction is necessary because you have removed the older jitter reduction which could select a section of the frames to use. I use Virtualdub Deshaker which has very good options to get correct stabilization.
3. NTSC 23.976 frame rate is actually 24000/1001 NOT 23976/1000. When I export uncompressed it is correct, but when I export Lagarith it is wrong. I have provided a metadata HTML report for both uncompressed and Lagarith output along with the relevant files output from the same source by MEP. This causes problems when exporting large videos as the lengths do not match. This has been reported before, and is still not fixed. The MP4 output is correct. Once Lagarith has been used for AVI output selecting other codecs for AVI also outputs incorrect videos. There is a picture of the error message for Lagarith ouput. The problem is obviously in the Advanced selection of the AVI output menu.