Childminders are quite used to children not eating :) I'm sure it won't be a problem and hopefully with the CM's laid back attitude, not having milk available, and seeing the other children eat she will start to join in more.
My son was exactly the same, only wanted me etc until he was much older. He was somewhere between 18 months and 2 before I could leave him with people. But if you go slowly and help her build up a relationship with the childminder it will help make the transition as smooth as possible for her. Are you doing some settling in sessions, including one where you stay with her? My tips: don't play directly with her on the settling in session but sit back and let her play with the CM and/or other children. If necessary do a few settling in sessions so that you can build up to this point. When it is time to leave her for the first time, explain to her (even if she can't understand) before you get there what will happen, that you will say bye bye and go away but she will have a lovely time playing and you will come back - you can practice this now, leaving and reinforce this key phrase by leaving the room for a few seconds, saying "bye" and then when you come back in announcing "I'm back!" - slowly extend the time so that it goes to you going to the toilet, then making a cup of tea, then perhaps leaving her with your DH or another relative while you drink the tea.
It's really important not to sneak off (she must see you go or it will make her nervous at other times that you might disappear!) so stick to this key word "Bye" and keep it very, very low key. No kisses or cuddles or even reassurance, this seems to make it worse. Just a breezy, happy "Bye bye! See you later!" and go - even if she cries, even if you cry! Try to look happy and unconcerned until you get out of sight.
It sounds odd but I found it really helpful to tell DS "bye, just going to the kitchen" or "Bye, just going to the toilet" and announcing "I'm back!" even if I was leaving the room for just a few seconds. It helped build up this certainty in his mind that I wasn't leaving unless I said "Bye" first and I would always come back.
Children who have their needs met (co-sleeping, feeding on demand, being sensitive to their "clinginess") when they are little grow into more secure and confident children when they are older. People who are disapproving now don't know what they are talking about - how can you judge a child's character for the rest of their life when they are only 7 months old?!