So it seems that in ZCM 10.3 you can't change the content repo to use NSS.

The docs state you have to MOUNT it (um, nss is already mounted), but I opened an SR and got this:

Thank you for contacting support. Since the content repo location is hard coded this makes doing what you want a little tricky. NSS has a limitation of being mapped to. What you can do is create a different volume that is not NSS and do a mount point in the content repo directory pointing to that new volume.

As an example:

Create the volume
Create the structure you want, ie,. /media/<new volume>/DATA
Go to the /var/opt/novell/zenworks/content‑repo
mount /media/<new volume>/DATA

The bottom line is that NSS can't be mounted. I hope this helps.