@Michelist I’ve used OBS but only in a very simple and limited way. Can it be configured to make timelapse screen recordings?
@Aganseo You’ve said that you have the canvas image sequences produced by the Recorder docker in krita. So a video editor, such as that suggested by @Lesqwe56, would be a solution.
There may be smaller and simpler video editors available for Windows and I know that the NCH Video Pad can be used free for non-commercial use.
Another solution would be to import those images as an animation sequence in krita and then Render them out to an .mp4 file.
That would use ffmpeg and it’s not been established if ffmpeg is working properly because it may be the timelapse parameters from krita that were causing the noted ffmpeg error.
Another way is to use ffmpeg with manual command line execution but i’m not famiuliar with how to do that. There may be somebody who knows how to do that.
Again, that would use ffmpeg.
The quickest and simplest way would be to try File → Import Animation Frames in a new document that was the same size as the image sequence size.
Then play it to make sure it looks ok.
Then try to Render it out to .mp4. That would tell you if ffmpeg is working properly for animation rendering.