Hi,
I'll chime in here (even though I'm a newbie). I found this Wiki article to be helpful in explaining feline diabetes and how diet, insulin, and blood glucose interact:
http://en.wikipedia.org/wiki/Diabetes_in_cats
As far as encouraging Cali to eat, I've been dealing with that very issue with Mookie, trying to get him to eat more lo-carb canned food (he'd much rather have kibble or wet with gravy). Several things have worked for us:
1) Add a little water to the food and warm it in the microwave -- in mine that's about 8 seconds. Make sure it's not too hot.
2) Buy some FortiFlora Feline, which comes in a box of 30 packets. Amazon has the best price, which isn't cheap at ~$20.00, but it works like magic! One packet lasts us 3 days or more, because I only sprinkle a tiny amount on his food, and I only use it when he's not eating enough on his own.
3) Buy a package of Pro-Treat Raw Naturals freeze dried dog treats, chicken. Both PetSmart and Petco have them for $7.99, and one package will go a long way. I crush a little bit and sprinkle it on his food, and he loves it. That's also the treat I use for his BG test. When he hears me handle the bag he'll come running at a full gallop, even if he was napping.
4) Frequent, small amounts of food. I know it's hard when you're not home during the day, but the way I do it is to put half a 3oz can of food into a small Glad Ware plastic container (Glad Ware Mini Round 4oz containers with lids), which are those lightweight ones you can buy at a grocery store. They come 8 to a package and are inexpensive. I fill them, freeze them, and then put 2 or 3 out in his food dishes for little meals overnight or when I'm away during the day. I leave them in different rooms so that Mookie can hunt for them, to provide some "environmental enrichment."
Hope that helps you and Cali.