Staff has been working to help him be more comfortable and to minimize his agitation. His hind end can be a bit sore (X-rays revealed a bit of a deformity on one of his hips), so we limit the pats to his front end. He was found to be scared of the full sized broom, so a small hand brush was tried. He can get scared when people move too quickly around him, so we aim for slow and gentle.
Buster still has his own room where he can be away from other cats, but recently staff have been opening the door so he can venture out if he wishes.
A nice enclosed porch area has been added to the building Buster lives in, allowing him to sit not just outside his private room but outside outside, where he can feel the wind in his whiskers. He apparently quite enjoyed the porch when he was let out there, staying for a few hours in this new territory before heading back to his room.
When I visited him tonight, he was welcoming and happy to receive a few chin tickles. And then he was done with me and my big camera, and let me know with a series of growls. Unlike when I first meet him in the spring, though, he didn't feel a need to follow and menace me on the way out.