The current grid spacing is 16x16 which should theoretically align nicely with the RS interface components (it seems that way at least) but since my screenshot has a slight offset it's... off, a proper screenshot should clean that up (I hope).
The grid will be customizable though (row height, column width, vertical offset, horizontal offset, etc..)
You can "snap-to-grid" move and resize layers , when I properly align the background and grid it should "snap" to certain RS components if not then I'll have to write a second snapping handler, which probably will be a piece of cake with the current architecture.
Thanks bb
Goal achieved