what did i do wrong in "other worlds"

[<3AGS<3]

I just played "other worlds" and at the end i saved the boyfriend just to lose him, and natalia went insane. I had not the full score so i think i did something wrong somewhere.
Is there a alternative ending???

[†AGSâ€Â]

Funny that everyone seems to get a answer here but i dont.  Come on, some of you sure played that game and can tell me how to get the full score and a happy ending...

[marlamoe]

It was very easy to find the walkthrough using search.

http://members.chello.nl/h.vangompel/o/ow.htm

[†AGSâ€Â]

Oh well, thanks so much. It never came to my mind to search for a walkthrough to see what i did wrong. Maybe cause i am not as smart as you are.  :

First thing was to have a look in the walkthrough, everythings been done like its in there, but i miss 4 points and alkis dies.
So how to get a less confusing and unhappy ending? or is there none?