R.S.
Take your time and follow her cues. My children were incredibly slow to incorporate food into their diets. GAS, diarrehia,etc. Both seemed to just have immature digestive tracts.
You may want to try apple sauce and pears, just make sure they are sweet NOT tart. Beech Nut seems to be the best quality in that there apples are always sweet and ripe. Don't forget bananas and avocados (when she is ready). You can mix pears or apples with squash and a little rice cereal and have a good mix of vitamins and iron. (I am assuming rice doesn't bother her--make sure you get rice cereal without soy--to rule out that the soy lethicin is not bothering her.) Oatmeal seems to bother alot of babies with sensitive tummies.
My kids also had reflux (not to say that your daughter does). But there are lists of foods available online to help you introduce foods in a slow manner. Blueberries (frozen organic from traders joes are great too--the seasonal ones from the northwest--very sweet).
Just try not to compare her to her playmates. Make sure you are spacing out formula and food (I literally had a food diary that I wrote down times amounts, etc. in). Don't give her formula immediately after food, just in case she is having problems with a slow digestive tract (that will cause heartburn, diarehia, and a very cranky baby).
One day at a time! She will not be eating only yellow veggies at 5 years. (oh, I found that alot of the green veggies are harder to digest--green beans, brocolli, peas, etc.) (oh and sweet potatoes definitely increase bowl movements--that is totally normal).