Personally speaking I would say avoid food in gravy anyways. Whilst some cats will eat it and be OK others eat it and it upsets their tum awfully.
My advice to you would be stop changing the food. Pick a food and stick to it. If you put out a small amount of food.... leave it there til the next meal and put down a little fresh food so its not going off. You will find that kitten will discover that you aren't going to be a complete walk over and change the food constantly for them and they need to eat what they are given or starve! which they never do.
Battle of wills, you just have to make sure you win!
Depending on age of the kitten we sometimes find that the whiskas kitten loaf is a good option as you can add water to change its consistency.
Stick with it and things will come good but if you change too much now you will end up with a mega fussy cat that is a nightmare to feed.
Good luck!