Trying to edit HDT hair

[theprepus]

Hi

As title says im trying to edit the hair caress, from HDT KS Hairdo, to eliminate the braid.

 

So im trying to do this using outfit studio and here is the problem, even without doing anything, only importing and exporting it ends like this.

 

 

So i would very much appreciate any clue on what is going wrong here, thanks.