Modify existing Unity game

1. I have a game in Unity which currently loads data according to XY co-ordinates I need it so it works with XYZ so the height of the object is also taken into account when loaded in the game. 2. Currently the grid is about 1000 X 1000. I need the grid to be a variable which can store data up to 1,000,000 squares x 1,000,000 squares x 1,000,000 squares. This grid will then be meshed around a sphere of the appropriate size to how many squares in XY. So I am trying to make a planet surface from the grid. 3. Currently the game moves players according to co-ordinates updated in Google Spreadsheets I want to be able to automatically move objects at a variable speed in slide motion (no animation) to the desired new co-ordinate (XYZ2) from the old co-ordinate (XYZ1). This needs to work for multiple game objects at the same time from my Google Spreadsheet.