If you are high by any chance or perhaps a lot of alcohol got into you, there is a small possibility to like this. Not to understand it, but to enjoy the pretty colors, scenary and really weird passages of time used here.
Dark Sisters is not really a movie, but more monologues than anything else, long descriptions, plenty of words used over and over in order to achieve a proper run time I imagine. I really wanted to find some purpose to it, to excuse it's budget and see the forest beyond the trees, but there was no forest, nor trees for that matter. If simbolism is the main theme here, it's just too much, you still need a plot, proper characters, genuine development, anything that keeps one's interest alive.
To me this movie is like watching a plant grow. I know it sounds magical but it takes forever and does exactly what I would expect. So why waste the time?
Dark Sister is one of the most pretentious and boring experiences I ever had, a movie I honestly wish I didn't encounter. I warn you, you will get very little out of this one. Like trying to get water from a rock.
Cheers!