Well I finally got my new PCBs from DirtyPCBs.com. I had all my parts from my Digikey BOM. I had some solder paste from SparkFun. And of course I also had a Polyimide stencil I ordered from OSHStencils. All in all it was a great success. The unmodified toaster oven performed it's reflow job great. All the LEDs lit, and the board to board chaining seemed to work great as well. More details on my blog.
A simple diffuser in front of those LEDs would create a very nice display.