Have you solve the issue eventually? I just encoutner this problem

oh, I honestly do not remember. It´s been three years since I´ve played it but I fixed it somehow.. or it fixed itself on its own maybe.. ah, I can´t recall what I did to solve it, damnit. Isn´t there some visibility option for HUD? To make it invisible? Or move it around.. or try to change the resolution. Some flashbacks are coming back now while I´m typing this. Not really sure, but try to change resolution and change it back, if that won´t work, then try to switch it into windon mode, not fullscreen. If that doesnt work, try to go into windows (windows key) or alt+tab or switch from screen to fullscreen with ctrl+enter and then back with ctrl+enter. Or try to restart the game. But when typing this now I have some memory of doing something like this every time I started the game. But not sure really.
Dang it.. I wish I could help some more :( I´ll try to recall exactly what I did, but meanwhile try this things, cause I think I did one of these and it worked eventually.

Fingers crossed!

Dont worry, I fixed it by delete all files under C:\Users\USERNAME\Documents\My Games\UnrealEngine3\MonkeyGame. Thanks for the reply ya.

Ah, okay. Glad you´ve fixed it.

Enjoy the game, now! :) ;)