A bit late incoming this reply, but for anyone else curious - sort of.

There are passwords that you get at the end of each level in the first game - you can enter these (unprompted) in the Intex terminal near the start of the first level and skip to that level. However, you don't carry over any of your power-ups, so no keys, no money, no advanced weapons.

I have figured this much on my own. However, I cannot get to find the terminal. Is it anywhere near the craft, in the beginning of the first level? or somewhere later on? Also, how long is the game? possible to beat in one sitting?

EDIT: I found the terminal: it's sort of black/grey with blue lights/leds. It turned out that I wasn't using a correct key to access it. It works with a BACKSPACE (instead of SPACE , like I had thought).
As for my other question: the game is rather short. It's around 10 - 15 levels. Definitely possible to beat in one sitting, but I don't think I could endure it. The gameplay isn't even remotely as fun/good as in the reboot or in Shadowgrounds or Alien/Zombie Shooters. It feels that the game is old and designed in a different way. Still, I liked the mazes - it was pretty fun to navigate through some levels. Well now, let's see that Tower Assault : ]