A question about the movie *The Box*?

Okay i seen it a while back (2 weeks or so) and me and my mom were arguing about it today. I've been looking around trying to find an answer but there were too many different opinions, so I thought i'd ask here. I understand everything that went on and why, my only question is. Was it aliens or some other being (like god) behind it. I thought when (Stewart) he got struck by lightning he was able to have contact with the spiritual world and have these other powers, the workers (minions, w/e) were under his control and when their nose bled that was him releasing them from some comatose state. Then the portal was like a gateway to the other side (afterlife, heaven, etc) and that kind of portal at the end was like some way to travel to where he was going next. Now that's what I thought was going on, but my mom said that he was working for aliens and that all the workers were aliens too, and that all the portals where a spaceship (or at least the one at the end). So which is it? I'm well aware it is a greater power behind it all and I'm also aware the movie takes place in the 70's when they started sending probes to Mars. Arthur, Arlington Steward, and the other guy who shot his wife (I forget his name) also all worked for NASA. So really both make sense, the movie is based around free will and about the decisions we make. Why would that have been a concern for alien life? Unless they wanted to see if they were worthy of trust or somewhere along those lines, also it talked about how it wasn't to late to make the right choice (like were Arthur was confronted with the 3 doors). When Arthur fell on the bed with the water etc etc, he said not long after (if I remember correctly) that it was a amazing place or somewhere along those lines (heaven). At the end of the movie he asked Stewart if that was the afterlife and (Stewart) he just looked at him and smiled. So really this movie has signs of aliens and a God like power. So after all that i'll ask again, was it aliens or some other being? Thanks :]