That's certainly a mouthful but yeah, I'm often browsing and downloading things with chrome on my second monitor and I have finally figured out what was causing my occasional freezes.
Basically if you finish downloading a file with chrome and then try drag import it while playback is happening it will just freeze indefinitely.
I understand not everyone does this kind of thing and the easy work around would be to remember to stop playback or just use the file explorer (actually come to think of it haven't tested if the same thing happens there) but I just feel like there should be some kind of precaution to maybe stop playback once it detects a drag release or something.
So as for the 'question' Can anyone else repoduce this? (so I know I'm not crazy) or does anyone have any insight into if this is not fixable as its a browser thing or something?
Are you still experiencing this issue? I will say that your workflow is a little unusual. Most people set up layers and animation with a bit more care and deliberation. That said, please file a bug report so that the team can reproduce and investigate your issue.