If you notice, you look at the sprites. You'll see that each position has 4 sprites..If you look on a Sonic game, you'll see that it has the walking sprites than switches to the running sprites. How would I do this?
Ahh, this is the best question yet..
What you will have to do is go into the scripting/coding of RPG Maker XP itself, and modify the graphic recognition script. Which in generalization I mean remodel the graphic recognition script from 4 columns or columns to 5 or how many more. Also I believe while I was searching on google for some scriptings for my small MMO that there was some script that over ride that default graphic recognition script.
Damn, google has billions of sites...Do you know where in particular?