I mix Science Diet 'adult' food with about 40% quality puppy food, 5 month old. Just trying not to have to much protein, as suggested by some I know.
To the potty training. Take her out as often as possible, trade off if you & spouse have different sleep/work schedules. When you take the dog out after some crate time, take her outside immediately. Give her a few minutes to brew it up. Unless the dog is laying quietly inside, I'd give her some outside time every 45 min or so. Stay out with her for awhile and give praise as called for.