How is land and sea chosen on the fractal globe?
The tool samples seeded 3D value noise on a sphere. A sea threshold marks about the water percent you set as ocean. Ice is taken from the highest remaining land until roughly the ice percent of land is frozen, then highland fills the tallest dry terrain.
Can I match the same world after changing projection?
Yes. Keep the numeric seed and the same water, ice, rotation, and octave settings. The underlying globe is the same; only the flat projection and palette change how it is drawn.
What rules does this map follow for D&D 3.5?
It is a visual aid for world building, not a simulation from the Player's Handbook or Dungeon Master's Guide. Use it for continent shapes and climate flavor, then place nations and adventures in your campaign as you normally would.