Toolbox Murders

I like bad horror movies. But at the end of this film I was left with a "huh?" resounding in my brain. Just unanswered questions:

1.) The old guy, Charlie (?). How did he know about the killer? Why was he allowed to live?

2.) The killer- okay so he "clawed his way" out of his mother's body. Then what? He was in a fire? He drank Ponce de Leon's fountain of youth juice? Whats with the face and the homicidal tendencies?

3.) Why was Ned and Byron allowed to live so long?

4.) Did Saffron eventually die, nailed to the ceiling? Or was she finished off later on?

5.) If there was no apartment 4 on any floor, why did they make their attempts to "hide" that so obvious? Why not just make the former #5 apartments #4's?

6.) Why doesn't Angela Bettis eat?

I just wish we had more of an understanding of the killer, instead of some quickly thrown in nonsense about a "pagan" spell (and once again spreading the negative stereotype of the pentagram). And what did the symbols have to do with anything? It seemed that she was following a map, but it looked to me like she was just finding the symbols and looking at them.