Sounds interesting, but the criteria's a bit unclear. Painting/drawing a level from paper and designing a NeoLemmix/Lix level are two different things.
* You say I should be creating a Lix or NeoLemmix level. Does that mean I should submit it using the corresponding .nxlv or .txt file?
* Do I have to insert the painting/drawing into the editor?
* Do I have to paint a picture which fits NeoLemmix
and Lemmings
and Halloween?
* Does the painting need to be photographed into a .png file?
* After I designed my level on the editor, does it need to be screenshot-ted into an MS Paint file?
This drawing is one that Namida did ages ago. It may not fit the Halloween theme, but would this example qualify for your contest under your specifications?