girkers
The answers are again in already published documentation, so please take the time to do some reading.
The answer is probably no. Again referring you to available documentation (the backup with dar article mentioned in the other thread), the catalog information of what files are backed up is in the last backup part file, so if the backup fails, then the whole backup is useless.
If you also read the DAR2 wiki article, it refers to how to enable the mc (midnight commander) plugin to allow you to open dar backups using mc.
http://wiki.contribs.org/DAR2You may be able to read the existing files, good luck.
By the way, the problem you are expriencing, is exactly the reason that the old backup is not deleted until after the new backup has completed. That way you still have the old backup available to use if something goes wrong with the new backup.
I strongly suggest you have larger backup media and/or have a second backup media that you rotate. Additional media is cheaper than the costs associated with the problem you now appear to be facing, ie lost data !!!