We all know that special effects cost money, but it seems as if they could have used the money they saved writing the script to get some better shots. The train is obviously a model in most moving shots, the helicopter is obviously computer generated, the alien looks like the one from the end of Spaceballs, except it's a decade later and Spaceballs had an excuse.
The only smart thing they did was blur all of the special effects to make them harder to see.
Not even the actors could compensate for such a poorly written script and it's pretty obvious they didn't really try either.
Please, don't waste your time. Please.