First thing to do is to fix the packaging. You can find how to do that here: http://cube.wikispaces.com/Sharing+Content
Now for the content:
Editing:
Well, it's decent, but it seems kind of... empty. I feel it could use some more detail.
Lighting:
Lighting just seems like you spammed neon lights in different places and called it a day. Half of the lighting entities don't even have sources such as a lamp or fire.
Flow: No. None whatsoever. You run into a box or wall every corner you take. Those vent jumppads are probably the worst thing you could ever do on a map. Some of the pillars to jump on are too close together, so you fall off all the way back down just to run into more walls and boxes.
Misc: You spammed too many particles above the lava. Kind of an eye-sore. Also, wtf? There's a YellowArmour that's physically impossible to get too.
Overall: I understand you tried on this, so I'll give you a 2/10 for effort.
