I tried the TF2 version, I looked in the source and see +grab was renamed to +grav. Both +grav and +throw do the same thing it seems, I'm not sure what's different.
I made a youtube vid of this in action, showing what an engineer can do. Its an empty server with bots for the demonstration.
http://www.youtube.com/watch?v=_Vb6L27h0NI
I can see this plugin has a lot of potential, I can't wait until someone really refines this so its limited somewhat. I'd love it if only heavy's could use it, and they could move sentries short distances or something.
This "moving stuff around" stuff is pretty neat!