here's a rough cut of Sunloft, it's not fully tested, there's one known jumping bug where your jump power doesn't appear to carry over, it seems to fix if you get hit or double jump, i'm working it out.
http://www.newgrounds.com/dump/item/b9 d34024b91665a12de91dfdba836d21
Xiphon
wow there's a bunch of bugs in that, play that at your own risk, jeez,
things to note, most of the problems deal with the level itself, not the engine