Look at the MB64E_Presets_OffsetLEDPatterns in mb64e_presets.inc.
You just have to modify the patterns. For example I changed them for 13 LEDs. Pattern #1 then looks like this:
;; LED Pattern #1
LED_ENTRY b’0000000000000001’
LED_ENTRY b’0000000000000011’
LED_ENTRY b’0000000000000011’
LED_ENTRY b’0000000000000011’
LED_ENTRY b’0000000000000111’
LED_ENTRY b’0000000000000111’
LED_ENTRY b’0000000000000111’
LED_ENTRY b’0000000000001111’
LED_ENTRY b’0000000000001111’
LED_ENTRY b’0000000000001111’
LED_ENTRY b’0000000000011111’
LED_ENTRY b’0000000000011111’
LED_ENTRY b’0000000000111111’
LED_ENTRY b’0000000000111111’
LED_ENTRY b’0000000000111111’
LED_ENTRY b’0000000001111111’
LED_ENTRY b’0000000001111111’
LED_ENTRY b’0000000011111111’
LED_ENTRY b’0000000011111111’
LED_ENTRY b’0000000011111111’
LED_ENTRY b’0000000111111111’
LED_ENTRY b’0000000111111111’
LED_ENTRY b’0000001111111111’
LED_ENTRY b’0000001111111111’
LED_ENTRY b’0000001111111111’
LED_ENTRY b’0000011111111111’
LED_ENTRY b’0000011111111111’
LED_ENTRY b’0000011111111111’
LED_ENTRY b’0000111111111111’
LED_ENTRY b’0000111111111111’
LED_ENTRY b’0000111111111111’
LED_ENTRY b’0001111111111111’