In the full version for sure. Not in the Prototype though. However, you can hack your entities, so to speak! If you go into the entities folder of SailorXv3 and then open up the text file of your entity you can replace the numeric color values with hex values!
For example, the first line in your entities for SailorXv3 is probably as follows:
Everything between the first two semicolons is the color. So to make her body red you'd change the line like so:
PS:If you open the text file and its all in one long line then I recommend opening it in a different program, like "Notepad++". This will correctly split the lines, which will make the file much more readable.
Does that work for you?