do you put out numerous bowls of food?
i give all my crew their own bowl of food as opposed to a group bowl/bowls. i do this for a couple of reasons. first it is a way that i can control (to a degree) who eats what, i have a female (mommie) that every once in a while throws up so i try to give her gluten free food. also, she is somewhat of a glutton so i can give her a little less than one of the large (+/- 15 lb) boys. the separate bowls also helps to keep the peace, although now my crew has been together long enough that that is not really an issue. another reason for separate bowls is that in the warmer weather i can de-worm them and know that everybody is getting their meds.
as far as trust, mommie was sort of relocated to my colony (long story) and has been feral a lot longer than the rest. it took probably 6 months before she would go to the food if i was within 100 feet. i would just walk away after putting the food down but still keep looking at her. once she went to the food i would stop and just watch her eat and slowly take a small step back towards her. as time went by she would come to the food when i was closer to her. now, she comes and sits right outside of my back door waiting for me and even lets me pet her and rub her chin on occasion.
keep at it, patience is a virtue and feral cats are virtuous.
"In studying the traits and dispositions of the so-called lower animals, and contrasting them with man's, I find the result humiliating to me."