An excellent game (and prequel to Don't Escape 3 heh). Brilliant retro-esque graphics and score.
To those that are STILL having trouble with the game on Hardcore, invest your crystals in Refinery upgrades. Sure it might be difficult without early cannon upgrades, but try your best to maneuver around enemy fire. After that, get Hull Nanites (Did you know this also helps recover your vessel's HP too?), and focus on getting Compressed Shotgun upgrades. This will help you heaps when dealing with tougher insects.