How Prevent 'Add Video' From Deleting Last Frame?

I have a set of PDFs that contain hundreds of MOV videos that it now seems I must discard since my readers will be sorely warned against Quicktime with a message so stern that it will scare them away. But now that I'm re-doing them all in H264 using the latest version of Adobe Acrobat DC, I have two big problems:

1. Is there still no way to set DEFAULTS for the video parameters I want? I have to enter the identical choices (Floating window, dimensions of screen, file to use as icon, Controls, and Opacity) the very same choices, time after time  after time. I was hoping that by now I could just default these. As it is, I am forced to repeat the same choices hundreds of times in a process that eats up several days of my time. I've requested this fix before, and I still don't see it in the latest version of Adobe Acrobat. Am I missing something? Is there an expert who can tweak my installation to make this possible?

I'm not optimistic about that since I have asked before. But please tell me I can be optimistic about question number 2:

2. With the old way, now deprecated as 'legacy', I could load a video and be assured that the video would be loaded as-is. Now I find that loading an MP4 (H264) video via the Add Video tool chops off the last frame. This is an AWFUL outcome. My videos are all of sentences in American Sign Language, each one about 2 to 3 seconds long, to which I have provided sub-titles for each successive sign since my readers are linguists who want to study how the language works but do not know know the language themselves. It's tacky and confusing to have the sub-title (in effect, the label) of the last sign in each sentence linger on the last screen. It should disappear so the reader can now reflect on the full sentence without this distraction. Is this just a bug or is there some simple way around it?

One fix, of course, would be to make the sub-titles (the Text Media item) one frame shorter for each sentence. But there are hundreds of them that I would have to re-build one at a time and that would be a huge job.