I love me some Beyond the Seventh Door (haven't picked up the DVD yet, but I've seen it before) but do agree the cover art is a tad misleading as it's far from horror but still a fun, odd thriller. I can understand your disappointment if you went in expecting a horror movie. Best way I can describe it for people who haven't seen it is that it's a late 80's Canadian television-style movie version of Saw/Cube starring a Yugoslavian-Canadian Tommy Wisseau doppleganger.
I enjoyed it. It was quaint and fun. A few scenes feel like they go on forever, like the girl running around while the room is flooding. As far as SOV movies go (I'm not sure if it was SOV though, or if it's just a video transfer?), I thought it was pretty ambitious and well-done. I doubt I'd watch it again, but at 77 minutes it's a breezy watch. The extras weren't exactly enlightening, the main actor keeps rambling on about cats or something. That said, it does feel like something you'd stumble across on PBS in the 90s.
Dread Central reviews Beyond the 7th Door: http://www.dreadcentral.com/reviews...eview-no-budget-s-o-v-canuxploitation-finest/