If the "Virtual Arcade" option is still greyed out, download a specific "Unlocker" XEX or use to unlock the XBLA titles embedded in the container.
If you need a full article for a blog or forum, I can write a detailed guide for you. Just let me know the target audience (beginners or advanced users) and any specific angle (e.g., preservation, modding, retro gaming). Namco Museum Virtual Arcade -Jtag RGH-