Hi Alan,
I'm more than happy that you were able to finally restore that course. But I cannot leave this to end without commenting 2 (important) points:
1) Setting the value to 2000M is insane. In fact, the default 1M is roughly "1 million chars baby". So 16M should work without problem.
2) Perhaps the problem is that, in your .cnf file above, you are setting the max_allow_packet value in the [mysqldump] section? If so, it only affects dumps. As I commented above, it must be "under the [mysqld] section of your config file".
Again, happy you got it done, ciao