Join the club. Ds is now almost 20 months and a similar behaviour started around 15 months.
I'm lucky as he will eat fruit, have you tried hum zingers? You get them in the cooking section of the supermarket, they are basically dried apple with a bit of different fruit mixed in. Ds hasn't touched veg for 4 months (so he thinks) I've been hiding it in muffins.
I was terribly worried at first, but I weigh him every 2 weeks on my scale and as long as he is gaining weigh there is no problem, however, about the vit drops, I did give him some, but put him on Formula again, he takes a bottle at waking and again bedtime, it contains all the nutrients and vit and minerals we so worry about.
The pale poo could be because of cow's milk. Her body might still be learning how to digest it. However, if she seems sick as well you should have it checked out.
I know this not much help, but at least you'll know you're not alone.
I also give ds yogurt pancakes for tea sometime, put a tablespoon of maple syrup in for sweetness, at least they contain, protein, calcium etc.