Permissions problem

[fork]

New iMac with El Capitan 10.11.3. Superduper 2.8. Been using SD since time began. Everything on the iMac was installed fresh. I did an SD backup to a USB key before I started adding apps and stuff, and that worked fine.

I just attached a new USB3 external HD with partitions and backed up both the iMac internal Fusion drive and an SSD external where I keep my files, each to separate partitions. Afterward the source drives permissions changed, eliminating my "Me" account completely and forcing me to enter a password for everything. But the backup drives still had the correct permissions. I did fix it but now I'm gunshy of doing another backup.

I noted that the most recent download on your main site was the same 2.8 that I have. But I did see a November link on your blog to a beta version 2.8.1.

Is this the fix? Or did I miss a setting I now need for El Capitan?

[so far, I really hate El Capitan - both my 2011 MBA and my 2008 MacPro running Yosemite are snappier (in the Finder) than the brand new 27" iMac running el Capitan]