Hello! I have loved using LRTimelapse; such a fantastic software! Thank you so much for this gem.

I've updated to 5.5.3 and I'm running it on a 2019 iMac with macOS Catalina, version 10.15.7.

I originally loaded a folder of time-lapse files into LRTimelapse, and I look for the intervals to see where I may have started a second time-lapse or look for slight bumps in the photo when changing settings on the camera. Then I separate out these batches into new folders that I then reload into LRTimelapse. Sometimes if the old XMP files are still there, I'll delete those (and remove the photos from Lightroom so that I may reimport with the new keyframe info from LRTimelapse) and try to start from scratch. So, I selected key frames, saved, imported into Lightroom, made my photo edits in the key frames, saved the metadata from those key frames, reload in LRTimelapse, select Auto-Transition, then select Visual Previews. The initial preview lum does not vary very much; however, the visual previews seem to be adjusting way too much in adding exposure and then lessening exposure, thereby creating huge amounts of unneeded flicker that was not in the original time-lapse. I did shoot this sequence in Aperture Priority, so that the exposure time lengthened as it got darker, until I reached 2 seconds of shutter time, then I switched to Auto ISO for the rest of the sequence. Because the exposure is maintained every shot, I don't need to use the Holy-Grail tool in post production. So, I don't know what whether the auto-transition or visual previews is getting confused somehow or if I need to do something differently. I've seen this once before when I used shutter priority a few years back, and that made sense because the aperture jumped around, but in aperture priority this time, the shutter speed slowly and gradually changed over a longer period of time.

I've attached a couple screenshots. If you would like me to email you my log file, I can do so. Thank you for your time! Much appreciated.

Hard to say without logfile and screenshots, but my first approach would be to give it a clean start via "Metadata / Initialize" in LRTimelapse. Remove the sequence from Lightroom and then redo the workflow.
1.) Take care to not mess with the predefined gradients: only use those for editing, don't remove any, don't add any.
2.) Don't edit too heavily with non-linear tools which might introduce contrast flicker: https://lrtimelapse.com/news/use-the-new...me-lapses/

See, if that helps. If not, please send over the log (info menu/show log) and some screenshots to support(at)lrtimelapse(dot)com.

Thanks for your quick reply and information, Gunther! You were right. That article on using the tone curve did the trick. First time I've ever run into this problem. I appreciate your time and hope you are well!