Hi!

I've been sculpting on a CC mesh in Zbrush and when I replace the original mesh with the new one, this happens:



This is the starting mesh:



And this is the OBJ I'm trying to replace it with:



I haven't added anything to the original mesh to keep the number of verticies the same, and I've been successful with this workflow before. But this time there's something wrong.
What causes this? And what can I do to fix it?


Here's an example of the other more extreme alterations I did that were successful.