Not sure what it could be, but you could try resetting Xforms and converting to editable mesh and back to editable poly. these scripts might be helpful http://www.scriptspot.com/3ds-max/scripts/transfer-uv http://www.scriptspot.com/3ds-max/scripts/morphix (only if the vert order has been changed somehow)
amisima: how do you use mudbox to change vertex order? i agree that vertex order is the most likely cause and easy to terst using the morph modifier. you can fix it in max using the morphix script.
Hello, Like Joost said, the possible problem can be different vertex order. You can test this by using Morph modifier. Both scripts above can help. Another way to fix bad vertex order - Mudbox. But there is another possible reason: different triangulation. Example: http://i.gyazo.com/bc9ac2ab4d30c04b10165de8391dec11.gif…