Okay, try this. I had to do this once. Unzip the theme on your computer, then move the DarkEdgeEriz.zip into the Android Themes folder on your SD card. Then open MM, start checks and click existing theme. It should show the name of the folder, something similar to what it was originally named, and it should be a blue folder that looks open, click on it, if it shows a list of items look for a apply all button, if it shows another folder, click that one. You want to apply the .xml which will have a big green M next to it