I checked in 5.4.4 and 5.5 and it seems to be OK for me. I downloaded and added a pumpkin in 5.5.
I also check on the Desert Western Cliff Sheer XL 09 and I get the Download/Add buttons.
Edit: I did see a message when I started Bridge in 5.4.4 that there was a new version of the plugin, but it still worked without updating it.
