Well i'm another Portuguese fan...
Tugas ao poder!!!!
And the movie wasn't that bad, but the low budget was really noticeable.
The notion of time when the aliens pop out from the sewers and the city is completely overrun is very short, and i'm not even mentioning the "instant" chestburster to adult morph from the predalien and other aliens.
This movie would really benefit from a larger timespan, it rushes to much, a trademark from most alien movies, is that the development takes it's time, even in "Aliens" we can clearly see this (when i mean development i'm not just talking about character development, for example the battles in Aliens had some time between them, it helped to increase tension). Also the "shaky cam" action scenes were really bad in my opinion, i guess it was an attempt to avoid to show the aliens too much, since the suits didn't look that cool in fluid motion, all turns to budget again...
Well another thing not mentioned in the forums, if the movie story was like "Alien 5" with a single alien making havoc in the city, with an "Alien", "Alien 3" kind of terror tone, it could have been a really cool movie even in low budget.
For all that know portuguese: Somos os maiores!!!!!