Backups before SLD Content Upgrade

Hi Team,

There are new run-time systems coming into picture with 7.31. SLD is 7.3. So we are upgrading the SLD content (cimsap & CR Delta as per 669669 ).

The problem is our backups (all kinds are failing). I was able to have an unversioned backup, but System export and CIM Model (both full and incremental) are failing.

1. Can we proceed just with the Full Backup (I guess this is what is referred to as the unversioned content)?
2. Whats the importance of CIM Exports?
3. How is deleting Old change logs (prior to the last full CIM Export Date) affect anything?

Regards,

Varun