A couple notes on SR-5,
It doesn't appear that SR-5 is the direct cause of many of these problems, rather, doing a hard reset (thus resetting permissions) of the unit.
Additionally, don't do a hard reset if you have any files in your "homes" directories... especially if you do a dumb thing like myself and forget to do a backup first (8 years of finanical records... gone.) Once you hard reset, you lose access to the homes that were created and the rights are not re-established when you re-create your usernames (even if identical.)
As for the FTP issue, it looks like users don't have access to system root (or drive root.) As such, you are unable to see VOLUME1 or the contents of VOLUME1. However, once you add another directory (i.e. Public), users have had permissions set to these items thus you can access them. Inconvinent to say the least but good catch by the last poster.
This raises another concern for this NAS unit... What if the unit fails and you have to switch boxes (put the hard drives in another NS4300N.) Are the user rights written to the drives or in the ROM? If in the ROM, users transferring drives would always lose their "homes" directories. I can't believe this is a desired goal.
Feedback is always appreciated. If there is any chance that I merely don't have rights (even as "admin") to the old homes directories and the data is still there, someone with telnet access could save me a LARGE headache.