"columbus" workaround
I have found a relatively simple way to look at the whole map, though it is more for modders than for cheaters, but I thought I would share it here, since it has been brought up in the discussion here, in the hopes that it might be useful to someone:
Create a game and play as Sweden - you can choose any time period. Save the game.
Open the savegame in a real word processor. Even if you usually use notepad, use a real processor - trust me.
Note: below, the string <space> indicates a single "space" character. No other whitespace should be present in the search strings except as denoted by this tag.
Search and replace:
Search: discovered_by={
Replace: discovered_by={SWE<space>
Replace all.
Search and replace:
Search: discovered_by={SWE<space>SWE
Replace: discovered_by={SWE
Replace all.
Save the file.
Load up your game in EU3 and view the world.