Best practices for long-running installation

[A]

I'm using a 5D Mkiii with the new 1.2.3 ML build via HDMI to a Blackmagic shuttle for a long-running interactive installation in a museum. I'm trying to set the camera up to be easy for the staff to use and to run the duration of the show with minimal bother.

Is there a way to keep the HDMI feed up indefinitely in a way that is robust to restarting the camera? So that basically I could have the staff turn the camera off at night and just fire it up again in the morning? Currently I'm using the sticky-half-press trick and it seems to have not lasted the night last night (distinctly possible the button was bumped.) Also, the sticky button setting seems to get reset periodically in the menu without restarting the camera... Would I be better off physically holding the button down with something?

What are the risks to the camera from running indefinitely, if any? LCD burn? Memory leaks/crashing? Are there any other settings that I should use to reduce wear on the hardware?

Lastly, for the purposes of reliability would I be better off running an older version of ML?

Thank you for your work on this project - it's really incredible.