Do you plan on flashing a lot of roms? You could just have wmdc sync files if that's what your main goal is.
I don't recommend SPB backup to restore files to different roms. I only use it if I'm on a pretty good rom and I want to check out a new release. I'll backup my current rom just in case the new rom doesn't work out. Then I can flash back the old run and restore my backup with minimal downtime.
If you want spb backup b/c you want to just restore your settings when flashing different roms, I'd recommend looking into sashimi.
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