Game Dev Tycoon Download

So I buyed Game Dev Tycoon before you got the code on steam (like 2 - 3 years ago) and now my Problem is that I can’t download it because i got an new PC this christmas and now I can’t download it because I never got it on Steam because as I said I buyed it at that time were the game had an own launcher. So how can i download it again?

There should be a download link in the e-mail you got after purchasing the game

You should have gotten an email from the orderings (is that the word? orderings? orders?) company Fastspring containing the steam key, I think.