Thank you so much, Agelyk!

The menu colors were part of the .png, as there was no "FILLCOLOR" on this theme i wanted to copy the menu style.

So i went to my W7 theme, exported Menu_PopUpItemImage.png, Menu_PopUpSubMenuImage.png, Menu_PopUpCheckBackgroundImage and a few others i found relevant and imported them all in the corresponding locations of the W10 theme.

The menu now looks as i wanted!

Thanks again!