Wow...looking at the achievement percentages it seems most people got as far as beating Tempest then quit. Though more people have completed ZoE1 than 2. Maybe people thought the game was boring and skipped the sequel..the fools. After the first "Beat Viola AI" achievement the percentages drop significantly.
Maybe it's all the Americans having to adjust for the increase in difficulty. --- "The problem with quotes on the internet is that you can never be sure if they're true" - Abraham Lincoln