Why did my Afinia printer create this mess?

I've only printed a couple of things with this new Afinia printer. The calibration model printed ok a couple weeks ago. Tonight I tried to print this model of the Enterprise:

[www.thingiverse.com]

I loaded the design in the Afinia software, scaled it back to half the size, and started printing. It said it would take 2 hours, so I came back later with about 15 minutes to go, and stopped the print job when I saw it. For some reason it was joining the two halves of the disk with a thin "roof", and the parts that were supposed to be printed between the disks turned into a coiled mess. The two engine pods were joined for some reason.




It's supposed to look like this:

Any ideas why it printed that way? Also, it's a bit hard to see, but the bottom of one of the disk halves seemed to peel up (did not stay flat against the perf board). The opposite disk half did stay flat against the board, but had a couple of it's layers separate.

The strange "roof" that got printed between the two half-disks is cool in that it's thin and straight - it didn't need support to span across the space between the disks.

The STL model is not very good. There are a lot of inverted elements, including the two saucer sections as well as the parts of the nacelles that were walled together in your print. You could try fixing the file in MeshLab or Netfabb.