to be honest, i tried to push to the limit the ceramic materials with the Elegant Dog.
In the beginning i imagined this model in black glossy ceramic or in steel, but at the moment the metal materials were a bit expensive for me.
In the end i rendered the model with a glossy material, similiar to the feel of the glossy ceramic.
Probably my mistake was to work before reading the guidelines, because i noticed that many things were wrong, so i tried to fix the model as best as i could for the guidelines (i have fixed sculpting and renderings).
I knew that probably something would go wrong, expecially for the legs, and for the fact that the model is hollow inside, but i made those components more robust.
My first costumer bought in dyed plastic (the small version, not hollow), and after 2 or 3 "your model can't be printed" we decided to try the ceramic material on the bigger one. Theissue with the small dog is that Shapeways had some problems to clean the inside of the model and it were impossible with a small hole (i used his navel). In the end i closed this model and now it's fully printable, but me and my costumer (that really woth 3 thousand of thanks for the pacience) decided to try the 15cm version in ceramic.
After 2 or 3 re-order i was sure that some fixes were necessary, i always try to take the advantage of this because Shapeways always send some images and advices for let the model survive the next print.
In this case fixes were not needed and Grrrrbob as promised sent me some images of the
Elegant Dog (15cm) in Avocado Green Ceramic
I have not much experience, but what i can advise is to try and re-try to print model if you believe that it can survive in a specific material