Hi Sunshine4, I don't know that I can offer you much advice, but I thought our story might give you some hope. I worried about all the same things for my dd5. She enjoyed pottering around at preschool last year, but didn't really have any strong social connections. She was great with adults and was good at following rules, cooperating etc., but just didn't really play with age peers unless she had to. The psych who tested her didn't have any concerns about dd socially either.
I worried about school this year and whether I'd find her wandering the playground alone - one thing in the confines of a pre-school playground, another in the context of a space big enough for a few hundred kids. This year she started in a grade 1/2 composite, skipping kindergarten. She would have been one of the youngest in the grade even if she had been in kindergarten, so now she's between 12 and 30 months younger than the other kids in her class. We're something like 4 weeks in to the term and she has a group of about 4-5 friends she regularly plays with and really enjoys. I think she just needed to find some older peers who shared her interests. So I would perhaps investigate whether entering at grade one might suit your family (if it's possible).
Best of luck.
