Hi,
First, I’m french, so, I’m sorry for my bad english ! 
I am on win 7 ultimate 64bits (customized) and installed scrivener a few minutes ago.
I have an issue with the “L” letter. It doesn’t appear like in the screen capture bellow :
Thanks
Pandore, what do you mean by customized? What exactly is customized on your machine?
Win 7 is customized with a mstheme. May be it can affect Scrivener… or not. 