Here's a quick run through, someone correct my steps if I'm wrong! I just do it until I figure it out lol.
1. Download the roster file onto computer.
2. On Xbox, in mlb2k13, save a default roster file to your usb.
3. I believe you have to unzip the ROS File. Make sure you can locate the specific ROS File in a folder.
4. Open horizon, click the tools tab, then package manager, click the open tab, open the roster file from above.
5. Open the default roster from your usb.
6. Copy the profile ID, Device ID, and Console ID from the default roster into the new 2k13 roster.
7. Click save rehash resign, click save to device.
8. Take out usb, plug into Xbox, load roster from device.
9. Enjoy current rosters for a 4 year old game!
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