Umm...What's BOD? Are you talking about the regulator? Are you suggesting that I just feed the +5v regulated line from the battery directly, at 6.3V?

The difference seems to be minimal, and I suspect it will cause no damage, but is that what you mean?

Incidentally, I have been looking for any possible difference between what I am doing and the published circuit. The only thing I can see is that the regulator is flanked with a couple of 100nf bead capacitors, and I am using 100nf polyester. Interestingly, the data sheet for the 7805 regulator suggests 30mf capacitors, but I am following the published design. Perhaps there is a problem there...?