Hi Olga, some more details on your question:

> It has been over a year since you discussed this problem.
> Have you resolve it?

I just tested with the latest version of ZBrush (version 3.1), and I cannot repeat the problem there so it looks like it has been resolved.

However, please note that it is normal and expected for unwelded meshes to behave like this, those are meshes where polygons have their own points which are stacked up on top of their neighboring points, rather than polygons from different sides sharing one single point.

If you want to avoid this kind of behavior then make sure you have created a welded mesh - to do this when you export from MoI make sure you have the "Weld vertices along edges" option turned on (checked):




Or another option is to use the weld option directly within ZBrush. If you have polygons that are not moving together with one another, you can use the Weld tool which you can find in ZBrush under the Import section on the right side:



That is another option that you can use to edit an unwelded mesh that has disconnected pieces into a single unified set of polygons that share points with one another.

- Michael