I recently downloaded from thingiverse "sexycyborg" stl. It sliced and printed fine at 1/3 size as a solid object. I tried to slice it as "vase" at the original size and one of the thighs was missing as well as other parts. Was this just a bad stl? or is there a problem with the mattercontrol slicer?
This is neither a bad STL nor a problem with MatterSlicer.
Spiral vase (assuming that's what you're referring to by "vase") prints the model all in one long extrusion. As such, it does not have the ability to generate, say, two legs if they are separated from each other at the first layer. MatterSlicer will draw the first leg and continue up the model in one continuous motion.
The bottom line is: you can't use Spiral Vase if you want to print this model.
Thank you for making this clear. I was confused as to the actual effect that "Spiral Vase" setting had on the slicing.