DirectX Game automation, Keyboard/Mouse input

Simple keyboard/mouse input into an old DirectX game (Everquest) to avoid continued carpal tunnel strain is not allowing me to do a simple task in this old game. I have written a basic keyboard/mouse input in C-sharp, but it does not work inside the game. I can help test the module once it's written and will give explicit details on which keys need to do what, and for how long. The initial inputs I need are as follows: Tilde, then hold E down, then click right mouse button, and move 20 pixels from right to left (pixel move will need to be variable), then let up on the RMB. I will send the compiled app, the code I have written, and a list of tests I have run with other apps (Autohotkey, Autoit, Etc) if need be.