Installing OFB will likely destroy your settings unless you take some precautionary measures first (move your neighborhood folder OUT of the EAGAME~1 tree until custom content is reenabled!).
Other than that, the sync timer is self-contained and has no conflicts.
I didn't even remove my downloads folder when I installed OFB, and when I entered the neighborhood for the first time (after enabling custom content and restarting the game), all the lot sync timer settings were exactly as I'd left them before installing OFB. It's working just fine.
Karen