Quoted from Mikespinball:

Hello,
Having the same issue. Island will work at times after the machine is off sometime. Was working fine, but just quit. Did some investigating and watched a video on YouTube made by TNT Amusements on a refurbished machine. They stated on the video that they had got one of the early Gilligan machines (back when they were new) and found out from the factory the green underside of the rotating island causes a reflection and gave issues for the opto to read correctly. They recommended to paint the underside black. I am in the process today 5/27/2020 doing that to mine. I am doing it in a flat black so that there is no reflections. I am hopping this will fix my issue of the island not working. Might want to try this to yours too. Will report back and let you know.......Mike