I don't what the correct format is, so i tried a couple of different DDS settings since 3DMTool exported it as a DDS, and DXT3 seems to be the only format that 3DM allows without giving me a Yes or No dialog option.
When ever i get a yes or no dialog pop up it's wrong format so i assumed the same in this case.
However saving in that format i have the issue that hair turns blue from afar:

Plus the file size of the DXT3 is only like 90kb while the original file from 3DMTool is 256kb.
So which format to use?