That .plg isn't the "official" one from bonienl. You won't see an update. If you want to use it, then you would uninstall the existing one, save that .plg to the flash and then install plugin and browse to the location and select it. But, if/when bonienl releases the update to the "official" version of the plugin, then you won't see that as that's not the ver you have installed.
Or over write the .plg on the flash and .txz with that ver, but then you're in the same boat again. Once the "official ver" is released, it won't see the updates.