Making a course with imported material public

Hi,
I have a couple of questions regarding making material public.

  1. First of all, are there any important rules in terms of copyrights and/or whether the original content creator likes his/her material to be accessed from the platform? I am wondering about this because, while it does result in views, maybe it isn’t the same because of advertisement? Also in some cases the imports didn’t work directly, but I had to upload the audio before linking to videos. Is this ok for public content?

  2. What happens when I make a course public and make adjustment to it later on. Specifically I am wondering about time stamp adjustments. I imported a nice series of more than 70 korean short stories (from a youtube channel) and while I work through them, I often adjust time stamps when I am in sentence mode. Would it even make sense to make something public, if I intend to make future adjustments?

Apologies If this has been answered before in detail.