We will be fine if we have a strong economy. Also we don't need to plan food for a lot of people for starters.
That is also the case. The population will only slowly increase. Don't know how many of the shareholders will actually move in to the island.
This could be the solution for the lack of space. We can make a floating Aquaponics.
Staple crops such as cereals cannot be grown efficiently using Aquaponics. But it is an option which can be explored.