It seems like you did not follow the tutorial correctly or the person doing the tutorial is wrong. There is a tutorial on this site. I have took some parts to make it easiler:
1: Firstly, open the program you'll be using (Gimp or Photoshop). I'll be using gimp for this tutorial.
2: Create a 'new' file, and make a 512 x 512 file. Also use greyscale, as it's easier. Greyscale is found in advanced options.
3: After opening your file, use the bucket of paint tool to fill your page in black.
4: To show where the parts of the area your using are (I'm using body for this tutorial), you should press 'open as layers' and open one of the reference files, found in feralheart>my presets>reference.
5: By pressing the little arrow, press 'grain extract' so you can see the body reference. The arrow is found in your 'layers' box.
6: Going back onto your background layer, press the 'layer' bar>transparency>Add alpha channel. You need this so you can draw out the markings.
7: Using your eraser tool, make out the marking you want. Made by forests is what I want on my markings. Must be on your background layer. (Oce done, delete the reference layer).
8: Now, go to your feralheart file. Your find a file called markings.cfg. Open that.
9: Once it's open, scroll to the bottom of the body markings. I'm using feline markings. You can find the canine lower down. Type what you want to call it.
10: Just press 'save'. Now, open up your feralheart, and your markings will be at the bottom of your body marks!
If you need screenshots go to this link:
http://www.feral-heart.com/index.php?option=com_jfusion&Itemid=2&jfile=index.php&topic=27569.0
