As I mentioned in another post earlier, I've been creating a hack to extract paths and positions from an Inkscape document to create free-form levels easily. Since there was some interest in the tool, I've cleaned it up some (it's still kinda messy) and put it on Github, here: https://github.com/kribblo/InkscapeToLevel
It's in Java and you need Maven to build it (or something like Eclipse). After that it's a command line application that takes a .svg as input along with some options.
You draw paths to create polygons suitable for collisions or similar and use images or rectangles to place positions of the player, enemies, the goal or what have you. The tool will write a Lua file suitable to load with "loadfile", and optionally also create a PNG version that could be used directly or painted on in another program before using in the game.
I expect it to be very buggy but by all means, please play with it, and feel free to fork and work on it as much as you please! There should be plenty to do and fix if you're up to it...
The README has more details, but could also use some love.
Also, ask if something's unclear, there isn't much in the way of docs.