You do have to wonder if this movie stemmed from a bet over whether or not you could make a good horror movie out of a 'killer glory hole'. The answer is; yes, but only if you completely change the concept and keep things vague enough for it not to become completely obsurd.
This lack of comedy and over the top-ness could be levelled as a criticism as well though. Despite the concept the film is mostly played very seriously, maybe this was for the best but then again some laughs wouldn't have gone amiss.
Overall this is a serviceable story about a struggling artist, but it relies a little too much on the out there concept getting it by and in the end the actual story comes across as a little shallow. Perfectly watchable if you like low budget horrors about downwards spirals though.