That all checked out, so I tried as you suggested, and made a new image 16MB in size. Worked perfectly.
For anyone who finds this useful. You need a rooted Android phone, in my case, I used my Nexus 5. Install Drivedroid from the Play store (unpaid/paid is the same).
- Skip the Setup Wizard, you won't need it.
- Press the "+" icon, and select "Create Blank Image..."
- For a filename, it can be anything. Leave it set as an .img, and set the size to 16MB.
- Leave "MBR Partition table" checked, and select FAT from the dropdown below.
- Start up your Xbox. On Drivedroid, the new image should be listed. Tap it, and you should now see the "Host Image" menu.
- Tap the "Writeable USB" icon.
- Once that's all done, tap the Settings icon on the bottom menu (2nd from the right), and in the Settings menu, tap the "USB Settings" option.
- You can either use automatic, or manual USB mode. Just make sure that either "Automatic USB Mode", or "Manual USB Mode", are set to "Mass Storage" (2nd from top). By default, it usually selects MTP.
- Plug in your phone to your USB/Xbox adapter, and on the MS Dash, navigate to "Memory".
- It should now say that the drive was not working correctly, and has been erased. This is what we want. Press, A, and you should now see the new MU on the memory screen. At this point, unplug your phone from the Xbox, and back into your computer.
- From here, it is the same as any other softmod procedure. I used Xplorer 360, which does work in Windows 10 x64.
Thank you guys for the tips, and hopefully someone else finds this useful.