Nice. I also do a lot of layer work. How did you attach the top layer and what design program are you using? I have trouble enlarging the back layer evenly. Looks great!
Loctite Epoxy. As far as making the layering it's pretty easy once you figure it out of course. I duplicate the part, use stroke and fill tools. I use the Thick line and increase it to .25 and then weld it. If it's a piece that has some lettering it in or design you will have to go in and node edit it delete all of them so all that your left with is the silhouette. click on the main part, shift click on the bigger part, C and E and you're done. There may be a easier way but this is how I had to figure it out on my own. I believe there are some videos on youtube on how to do it as well.