Hi Suzanne, that's a cool project, it should be fun to test it with the UP printer.

Yes, as long as your object is a closed solid (which it is, in your screenshot you can see the object type listed as "solid" in the upper-right corner), your STL file should be recognized.

The only thing though is that the little chain connector loop will probably add some amount of complication to the print, because having the main body of your pendant elevated somewhat above the bottom level will mean the printer will have to build a kind of support structure underneath it. That's not automatically bad but for some cases it might be better to have things like that as 2 separate pieces that you then maybe glue together rather than doing it all as one print.

Also it's possible that some of your details like the eyes and nose shapes may just be a little bit too small for the printer to be able to reproduce very well - it will try but it kind of blobs out melted plastic and if your detail is smaller than the blob size it will end up kind of just lost in the blob... Sometimes details that are too small just don't work very well with some kinds of 3D printing mechanisms.

It can take a little bit of practice to get used to the limitations of the particular print method being used, as far as knowing what kinds of structures and details are not going to be generated very well.

It's not like it will hurt anything to just try and print it, you just might not get a very good result with some kinds of things though.

- Michael