I haven't played LotRO in a long time, so I'm not up on the specifics of how the game functions anymore, but there's a thread here with a 3 on 1 script. It has a definition in it to set a master window, which I don't see in your script.

I wouldn't say HotKeyNet ever "forgets" what it's supposed to do. If anything, HotKeyNet can send too many things to the OS which can cause the OS or game to bog down and things can be skipped because they can't keep up. This is most obvious if you have too low of a ClickMouse delay set in your options and you use a lot of ClickMouse actions in rapid succession or in games where the window has to be brought to the foreground to receive inputs. The former can be fixed by adjusting the ClickMouse delays to higher numbers and the latter by either slowing down your spam speed and/or in some cases by inserting small delays in the keys so the client has time to come to the foreground and return.