To look at the replication changelog you need to use the cli tool "cl-dump.pl"

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwit5tqk5qLXAhVK7iYKHaacB40QFggmMAA&url=https%3A%2F%2Faccess.redhat.com%2Fdocumentation%2Fen-US%2FRed_Hat_Directory_Server%2F8.0%2Fhtml%2FConfiguration_and_Command_Reference%2FConfiguration_Command_File_Reference-cl_dump.pl_Dump_and_decode_changelog.html&usg=AOvVaw0EeBRb66mKeGlybKkp0z1O

Ok, thank you


2. How do I see the setting for the max life of a CSN?
There is no "max life" of a csn.

Ok, what brought this up is that about every week, one of the machines in our environment breaks the replication with messages like this:

[01/Nov/2017:17:12:52.815891904 +0000] agmt="cn=meToXXXX" - Can't locate CSN 59f9d98a000000760000 in the changelog (DB rc=-30988). If replication stops, the consumer may need to be reinitialized.
[01/Nov/2017:17:12:52.820619690 +0000] NSMMReplicationPlugin - changelog program - agmt="cn=meXXXX": CSN 59f9d98a000000760000 not found, we aren't as up to date, or we purged
[01/Nov/2017:17:12:52.828626595 +0000] NSMMReplicationPlugin - agmt="cn=meToXXXX": Data required to update replica has been purged from the changelog. The replica must be reinitialized.

So it made me think that perhaps the CSN record is removed too early? The ’76’ in the CSN is the machine having the problem. What do you think could cause problems of this kind?

There is replication purging and changelog trimming that uses csns in RUV's to determine what can be removed.  The admin guide talks about these in more detail.
3. How do I view a particular CSN (i.e. its contents)?
csn:

    59f9e547000200010000

Breaks down like this:

    59f9e547 0002 0001 0000

Yep, found that info previously, but thank you still!