Unable to import translated docx into Storyline to generate .story file

Hi,

I am new to SL, I exported the source .story file into xlf and docx, I translated the docx in Trados and now I need to generate the target .story file, but I get an error.

Trados didn't recognized the xlf, so I tried in memoQ, but again, when I try to import the translated xlf in ST, I get an error. Any ideas? 

Thanks!