2.4.6 caused issues recording on SD cards. Please downgrade to 2.4.5 if you would like to enable this feature. Users wanting to go to Youtube will need to use Manual RTMP if they want to record. This issue has been resolved for future releases starting in 2.4.7 (future release).
If you need to turn off the update screen to disable the update checker; on the front of the Vidiu go to System > Firmware Updates > Check for Update > Enable/Disable.