I assume that you wired the LEDS in series with the battery, correct?
Doesnt this drop your battery voltage too low? I thought Shoeboxes original battery was 7.5 V, so typical LED forward voltage is 0.7 V x 3 = 2.1 V or 6.9 V going to the board (with full battery).
I am thinking about modding mine to add a LED indicator (one), but was curious on this part.
Sorry to bring up a semi-old thread.