Thanks for the tip KSV, I had missed your patches so far and I'm sure they will come in handy.
However, even with the patched version of rtmpdump I still don't get a proper download of these videos . For instance, see the following result from the Jason Weston video I linked.
HTML Code:
https://mega.co.nz/#!FJ0BAJDQ!N96RuBB93GAf2NpcQXqg73wdCCtLHevVOlTBUXh7yAU
The issue starts at 1:18 in this case. It's only easy to spot for a few seconds since it doesn't show clearly with static picture like the presentation slides, but it is visible again from 2:24.