I believe there is some information in the manual about grouping and unit facing but i can't be sure.

In terms of adjusting unit depth you can click and drag obviously but i prefer to use the + & - keys. (dunno if it's different keys on other keyboards but mine is a UK one, check the manual) Remember though if you grouped the units before you change their depth, once moved, they will return to their original formation. What i do to get around this is select the group, adjust unit depth (using + & -), select a formation (shift-1 for example), then press "G" twice. This will un-group then group them in the new formation & unit depth. I have become quite adept at maneuvering infantry, most of my generals now have the Infantry Commander of Genius trait.

Hope this helps.