Partial Answer:
The Opinion of Hagaon Rav Yosef Shalom Elyashiv ZTL:
Source: HERE
Dec 14, 2010
Interesting Psak From Rav Elyashiv: No Kotel On Shabbos
A few years ago Israel installed a series of security cameras throughout the Old City. It was a time when there was a rash of stabbings, and stabbing attempts, in the Old City and the cameras were meant to both help catch the perps and to also discourage it in the future, as they will know they could more easily be caught.
The issue was raised that perhaps the cameras operating on shabbos would be a problem with those walking through the Old City on Shabbos to go to the Kotel. Rav Elyashiv was supposedly asked and after being made certain that it was not based on motion sensors and no lights were to be activated based on people walking by he paskened that people could continue to walk to the Kotel on Shabbos.
Kikar Shabbos is reporting, based on a notice in the Yated Neeman, that it seems the security system is not being monitored the way it was meant to be. Therefore, Rav Elyashiv has supposedly said that people should not walk to the Kotel on Shabbos, because they might be tripping security cameras. Until the system is checked to be ok, one should avoid it. According to Kikar, while Rav Elyashiv initially was satisified with the arrangements, at a later time he, or his people, tried to get the police to make some changes to some of the technological aspects of the system to satisfy some more machmir concerns. When the police refused to comply with the request for additional changes, Rav Elyashiv supposedly withdrew his support.
Obviously such a psak will affect thousands of people every shabbos. And not just those who are walking to the Kotel These security cameras are placed throughout the Old City and if the psak is really true as publicized, people throughout the Old City will have to stay in their homes the whole Shabbos.