I announce success. There was not really time for balancing, so the game might be very hard and dull or very easy and dull. But I'm still happy about what I achieved in these 7 days. And the game is somewhat complete experience with a goal, ending, quite nice looks, and lots of places to visit.
Play the game online @ http://dev.infiniverse-game.com/7drl/
Or download and play offline from: https://github.com/tapio/infiniverse/zipball/7drl
The versions linked above are the challenge versions and are frozen.