STAAD Foundation Advanced Steel Layers

I am designing a mat slab.

The slab Designer dialogue box allows me to set the top cover and bottom cover.  Does the longitudinal or transverse reinforcing have the least cover?

Are layers 1 & 4 always in the longitudinal direction?

Does SFA allow for the reduced capacity of layers 2 & 3 as they have a smaller lever arm (i.e. d2 < d1)?

Would like a quick response as this is my first time using the software and want to know I detail this correctly on a project please.