There are 2 problems witn me doing Overlays for the 510.
1. The most obvious, I do not have a G510, and cannot afford one, so I cannot make a Template.
2. There is just not enough space on the G510, or the G19 for that matter to do anything decent.
My best guess would be, you could paste a texture and that's it, anything more would be so small as to be insignificant.
ALL that you need to do is download AIDA64 (formerly known as everest ultimate)
In File/preferences/LCD yyou will be able to set up your very own custom display with all the relevant info you want, like custom BMP's, temperatures, % of usage and others.
When dealing with BMP's I strongly recommend saving as MONOCHROME BMP.
I'm posting pics of some custome displays I made, lol
All I need now is to think of a way to print legible overlays for the G keys and the winamp plugin for disco lights