If you haven't checked it, I suggest parts 8 and 9 of the Platform School Tutorial on the wiki page. They deal with enemies and enemy AI, and if you didn't look at that, that can be a great help. It offers essentially a foolproof way of setting up enemies and enemy spawn points.
Just looking at things briefly, a major problem is that your events for your spawn points are set up that only ONE spawn point will actually do anything.
What you need is the condition "For Each Spwan" [sic]
Because the way you have it now, only ONE spawn point will activate and destroy itself, leaving the rest to just kinda sit there.
Also, nowhere on your layout does the enemy actually, you know, exist. What you want to do, is put instances of your enemy outside the layout, with the Group attribute "Destroy on Startup"
Then you can probably put the enemy and the light object in the same container. Because your enemies just... aren't there.
Really, like I said, check out the tutorial. You may not be making a platformer, but I would highly recommend seeing how the tutorial does it, and learning from that. A lot of what is causing crashes for you is in fact just simple errors.