New betta-release: a few improvements: better interface, better music handilng, "crossfire" map, better co-op mode, and others.
A few more interface improvements to be able to port it to Android...

Added new screenshots.

P.S. I'd be very grateful if anybody could look through the game texts (spoilers! ) for errors and suggestions: http://forum.freegamedev.net/download/file.php?id=9712 . English is not my native language
Also I use x1.5 difficulty multiplier for co-op mode. Could anybody test if it's not too difficult/too easy?