Pretty fun game! At first I was a bit confused on all the different planet types, but this game has proven to be quite gripping. Is there a tech map somewhere, where one can see the upcoming technologies?
Unfortunately no, unless somebody made a fan version - you'll have to explore on your own! :) There are four tech levels, you can get 2/2/3 from the first three, and all five from the last level (if you can afford them).