4GB limit, chunk download, what to use to demux and remux?

[Derek Moss]

Not so much about chunks but I've downloaded and ran into the 4GB
limit as well (on Windows, NTFS). I'm not overly concerned as I only
wanted the ceremony before the athletes procession, which I've got but
I need to remux it (without re-encoding) to cut it at that point and
also because the timestamps (I guess) are messed up and I can't seek
in the video without it locking up for ages or crashing the player.

So could someone advise what tool would be best to use for this please?