Custom skins not working [SOLVED (not really) ]
What is this for, a screenshot? If you just want a red Wheatley for a screenshot then just use the console.
ent_fire !Picker color 255 0 0 (when pointing at him)
Think of all the things we learned
For the people who are still alive
i jsut want A FULLY RED WHEATLEY EYE ! not a screenshot , here are the modyfied files : http://www.mediafire.com/?oe9jjq9pjsec2bp
Wheatley uses a different model after the core transfer. Try searching in hammer wheatley_glados or vice versa. That is the model you need to change.
Aperture Science: We do our science asbestos we can!
tldr
if you want to change wheatley's eye red you have to make a mod, or a new model.
@supermarioportal: so are you not even making a custom map where to include a customized wheatley? is this just for the stock campaign? and is it only the red eye the only thing you want to change from all the game? 
2 things:
- As mentioned above your problem is that at first you've got the npc_personality_core entity, but as soon as you place it in the final socket it becomes the npc_wheatley_boss entity. Both must be using different models/materials... So first you must know what models is npc_wheatley_boss using (I'll try to check that myself later at home)
- The easiest way for achieving this is to to create a new folder under portal 2/ called portal2_dlc3 and, once you've found the models/materials that npc_wheatley_boss uses and customized the materials (there's no need for modelling or even hexing the models) upon your desire, you'll have to make a new pak01_dir.vpk file into portal2_dlc3 preserving the structure of folders of the original files (e.g. materials/models/npcs/... or whatever...). This must be done this way because of 2 reasons: vpk files overrides folders, and a dlc[n] has priority over the rest dlc[<n]
As Ben said, it's another option to create a mod and locate it into sourcemods folder, but I think above is a simpler solution 
useful tools and stuff here on TWP 
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