Holy cow, that 32 last night must have grabbed your attention?
You absolutely did the right thing this morning cutting back to .5u.
Your notes for today might explain why she's at 89 right now if she skipped lunch, but, it looks to me like you might be on your way to having a "diet controlled" diabetic cat.
You mentioned that she is almost off the dry? What I would do is try to get her the rest of the way there, and hold off on any insulin tonight, unless you see a number higher than 150, maybe even 200.
And post any numbers you get if you need advice on shooting or skipping a shot.
Tonight, assuming you skip the shot, try testing her just before eating, and then maybe an hour later. You might see an increase in BG from the food. An hour after that, test again. If it falls back down without insulin, then that means her pancreas is able (at least right now) to keep up with the increase in BG that would be caused by eating. If you see that, then you should be very encouraged!
If you are using a human glucometer to test her, "normal BG range" would be 40-120 for a cat. Oh, what kind of meter are you using?
Carl