If you got the link, made by "Get link", and you don't like the innecessary preview in browser, just add "?dl=1" to the end of the link
example: https://www.dropbox.com/s/1axoy96uwa80wko/matfyzak%20%281%29... - ugly preview page https://www.dropbox.com/s/1axoy96uwa80wko/matfyzak%20%281%29... - sane PDF link