Thank you, joecrow, this helped me, but now i have another problemI can confirm the the error you have reported, I get exactly the same when I try to install the plugin from the listing in MP Extension Manager. It needs fixing, devs?
I did find this post (2nd from last post, page 49) in a, not easy to find thread, that is dedicated to the KeyboardInput Plugin actual thread name is Generic Keyboard/Remote Input Plugin) which has a download of a version that does install OK, I have also attached it here.