I needed this exact same thing for my game. I needed to walk up to an entity, press the use button, and an image of that entity appears in the hud.
Assign this script to the entity's ai main field;
:state=0:hudreset,hudx=50,hudy=90,hudimagefine=gamecore\text\pressentertouse.tga,hudname=useswitchprompt,hudhide=1,hudmake=display,state=10
:plrdistwithin=50:hudshow=useswitchprompt,hudfadeout=useswitchprompt
:state=10:hudreset,hudx=50,hudy=50,hudimagefine=gamecore\huds\userimage.png,hudname=helphud,hudhide=1,hudmake=display,state=1
:state=1,plrdistwithin=50,plrusingaction=1:state=2,hudshow=helphud
:state=2,plrusingaction=0:state=3
:state=3,plrdistwithin=50,plrusingaction=1:state=4,hudunshow=helphud
:state=4,plrusingaction=0:state=1
For "userimage" put the image you want to appear in the hud, in the gamecore\huds folder.
Obviously you need to create the image you're going to use, in something like Paint.net or Gimp.
You can apply this script to any entity you want, the only thing that matters is placing the corresponding "userimage" in the huds folder.
