Nice work, a nice return to creativity in the mingling of music and video. Loved the Edward Gorey animation style.
What makes this stand out in the "documentary horror" genre for me if the sense of real character development throughout the film. The pacing was handled well, the production is as professional, if not more, than anything else in this genre.
Two sticky bits in the plot for me, the ending does beg some skepticism as does the sudden change in attitude that one character demonstrates with concern for the fate of one of their fellow explorers.
Overall, a good entry into the subgenre.
Sintel is extremely well crafted in terms of both plot and production, quite a feat to accomplish in its short running time. Well done!