Might be easy to fix. As best as I can make out, the strings are attached to a tailpiece, so I guess the bridge can easily be moved. Stop the string at the octave, and compare that to the octave harmonic. If the stopped string is sharp compared to the open string, then the bridge must be moved down towards the tailpiece; if it's flat, then move towards the head. I'm sure there are more knowledgeable people than myself here, who will be along shortly to correct any errors in this procedure, but you can see the basic principle.
I'd sort of hoist the strings up a little while moving the bridge, so it's less apt to scratch the soundboard or pull too hard on the strings.
This kind of string setup might need to be adjusted like this after changing strings, just because the bridge could move in the process. I personally like it anyway - it's slightly different in acoustical principle, the string's vibrations are transmitted against the soundboard rather than across it like in flat top guitars. Usually this design comes with an arched soundboard.