Problem with the construction of the shredder

Greetings to all. The first thing is to ask for forgiveness for my English since I am Spanish and we are very good at English.I downloaded the files of the pieces of the shredder of the page and I sent them to cut to a company of laser cutting. when assembling the shredder the pieces are out of square, the cutting files are not correct?

That photo is not very helpful in showing your issue.
The corners in the files are all square, so if your pieces are not, there is a problem in the cutting.  If parts are not lining up you may have them oriented wrong or need to do some d-burring.