How does my Editing look like?

Learn Premiere or Vegas (depend's on what you have) and go trough it from bottom to top play with it intensive for week and then try After Effects or similar and do the same. your skills should get better. and i advise you to buy some books on pro video editing and watch lots of video tuts.

The tracking looks slightly off at a few spots... It's not terrible or anything but maybe take note about it before your next project.

Otherwise it looks like you did a good job... Good luck in that contest by the way.

if you are using a low resolution source, then when tracking, you will have to manually adjust each frame for a perfect track.

If you are using a program like adobe aftereffects to track a low resolution source, I recommend instead getting autodesk matchmover. Instead of just 2 tracking points, it can do thousands of tracking points per frame. This allows for a smoother track with less shaking.

And if you can work with 3d models, you can also use image based lighting for the entire scene and make custom image maps that closely match the scene to add realistic reflections to the 3d object.

Here is example of matchmovers tracking

http://www.youtube.com/watch?v=6cNNX3ECiTI&feature=related

and here is a tutorial on tracking http://www.youtube.com/watch?v=ReXIipVo7LI

when you track a video, all you need to do is key frame the objects to the video. most 3d modelers have a smoothing ability for key frames so as long as you match the vector of a object, you can select 1 frame and place the object, then move forward a couple frames (as long as the vector and speed remains consistant), then move the object to the new position and key frame it. it will then create a smooth animation that is perfectly tracked.

And if you are adding 3d objects into the world and not having them follow something, then it is a simple process of dragging and dropping the object into the world and having it look fight in just a single frame, Since each section of video has a unique tracking point, it will automatically adjust the object to fit in the unique place where you placed it at.

PS, for best quality, use mental ray to render your final output.

PS but what you did so far is good work, especially with the program you used.