This is a bit sensitive to cultural influences. For instance, male facial characteristics have a clear regional variance, thus biasing the result in a particular population. I can tell from experience, I'm a male pushing over thirty with ridiculously androgynous features. I'm tagged as a boy by local population, and when I visit UK, I'm tagged as a 'ugly woman' :)
You will be fine, because you can tell the program that you're male.
However, the study has been using 244 Danes... I think you'll be right that cultural influences will be a defining factor here. I don't think the majority of people looks like a Dane. :-)