The way to disable the user pic is by using Skin Studio (SKS). You can download it for free from your account https://store.stardock.com/myaccount/products then, "View individual downloads".

Then, in Skin Studio, open the skin you wish to remove the pic from and...

Then,

Then, a window with the skin's name will open. If it has substyles, they'll be in a drop down list. You can choose. Try the main skin first.

Then, after choosing, this will appear:

Follow the numbered steps above. Save your changes and exit...

Then...this last screen (phew!) will appear. Click save and hopefully you're done. If the pic still appears, repeat the above for all the substyles. That should take care of it. Good luck! 
