Step 1. Go to top addons, and press OK
Step 2. Scroll down to get more
Step 3. Scroll the populated addons list, and press OK on the addon you wish to install
Step 4. Press OK on install
Step 5. Exit out by hitting the return key.
NOTE: YOU WILL FIND THE ADDON YOU INSTALLED IN THE TOP ADDONS SECTION IN THE MATRIX MEDIA CENTER.