I take it you didn't check the data structure page on the wiki?
game.DrawActionText = 0 -- don't draw action text
game.DrawActionText = 1 -- draw action text at cursor
game.DrawActionText = 2 -- draw action text inside rect
game.ActionTextRect is apparently unscriptable. If that just means that updating it will not get stored in the save file, or it needs the scene reloading to show changes or it's not scriptable in general, I don't know.