yeah stuff like that happens when my internet connection stutters try downloading the file again

You should also check hashes with this: http://pastebin.com/c9ZdUuQn (thanks to Xyem)

i have tried to download it on a different pc in the house, which also gave problems so its definitely the connection. (or somehow related to my gog account)

i have not changed any settngs, even reset the router to factory settings.

Have you tried a different browser?
Maybe an add-on to your browser is messing things up.

as i said i tried ie and firefox.

i have contacted my isp today and they said from their end the modem worked fine.
and that it might probably be the router and to try to directly hook up the modem to the router through an ethernet cable.
its all hooked up by a cable going under the ground so i couldnt try it, but somehow when i tried to download a game again today from gog it worked without a hitch.
so either its by luck or there was still something wrong from the isp side and they fixed it.

I am having this problem with Two Worlds as well. Which is odd since it's my first problem downloading anything, I even downloaded and installed Gothic 3 and Psychonauts with no problems today.