This particular hall sits in a village called Ha Tsuen and, until recently, was surrounded by a high wall giving it the enclosed courtyard that can be seen on film. Here is a reminder.
Note the white wall behind the railings in the following picture.
I'm sorry to say that during my research it has become quite obvious that some recent renovation work at the hall has involved the complete demolition of the courtyard wall, leaving the hall open to the street as you can see from the Streetview grab below.
This restoration was supposedly funded by the AMO and was really supposed to deal with structural issues pertaining to the roof and supporting walls, but no mention is made (that I can find) about demolishing the exterior wall. I will need to make a personal visit and see if they are reconstructing it, but to be honest it's not something I can foresee happening.
Anyway, this building is a gazetted monument which is supposed to protect it from demolition, I suppose the wall was either not included in the status or someone has really screwed up. This is HK, either is possible...
Here is the AMO info: http://www.amo.gov.hk/en/monuments_83.php