At first, I loaded the map on Forge and I had some mods on it. I thought that may have done it, but then I loaded on 10.2 vanilla, and then a couple different versions below but I still had massive amounts of missing chunks. Most of them are out in the open water in between the land masses. I checked half of the islands and they were all fine, but some of the small ones got caught up in the missing chunks. I even tried MCEdit and tried to repair the map, but it didn't give me any of the right options that other people were saying to use. I'm sorry you have to re-upload the map but I really have no idea what else I can do...