I suppose I should post a status update here on the Thing-O-Matic. We got it working (except for during the Maker Faire). Now it is printing extremely well using 1.75 mm PLA plastic filament. Having tried both ABS and PLA plastic, I don't understand the appeal of ABS. With PLA the parts print so perfectly and you don't have the curling problem because there is virtually no shrinkage. Also using PLA doesn't smell like a cat took a dump in your MakerBot, like with ABS. PLA is stiffer, which is better for a lot of applications. If I was designing a 3D printer I would not start with ABS as the basis. The most complicated thing I've printed so far is a pink differential gear system.
However, I have not had the best of luck with colors. I ordered purple filament, and I got pink (which Tori likes though). I ordered green, and got translucent green. I ordered silver, and silver is apparently the same as gray.