Please excuse me saying this, but 89$ for a PCB and a few LEDs is an outrageous price IMO... And a design that needs 12V or even 18V battery power isn't very smart, neither. A white LED needs 4V, older digital chips need 5V and if you somehow need more voltage you could use a DC/DC converter - but you can also save money making your customer buy a whole family box of AA cells...
Now I'm sure I could make it work if I had it in my hands... Pity I don't... But maybe you could post a few photos, I would like to help you.
So you are sure the battery pack is giving you the right voltage... Are you sure about the polarity (+/-) now? If those two things are right and that little LED stil won't light up, it's probably time for some debugging on the board.
Any chance you could PM me the instructions?
Good luck with your starship and have a nice day
Paweł