Tupine: That's one solution albeit you shouldn't have to jump through hoops like that.
Is it really that hard to implement an option to change the language through the in-game settings?
Seriously.
Anyway - if you're not opposed to do some ini-trickery:
On Windows look for a file called Engine.ini under:
C:\Users\[Profile_Name]\AppData\Local\Ruiner\Saved\Config\WindowsNoEditor\
and add:
[Internationalization]
Culture=en_US
for English. Save it and voila.
You can look up the parameters for the other available languages on the net.
Thank you Tupine! worked like a charm.