Well today I got my horse through the open field. She was nervous the whole way, but we made it. Got on a trail through the woods and came upon a fallen tree, a small tree. It was only about 10 inches tall, but she refused to step over it.
Heading back out, she got spooky again. I did learn something though. She goes ballistic after I get into her mouth a bit to slow her down. So I got looking at her bridle. The curb chain is too loose. The shank will rotate 90 degrees before the curb chain takes effect, allowing the bit to pinch, and in this case squeeze down on her tongue. The other bit I used would gouge the roof of her mouth. So as long as she's relaxed, and I'm not putting pressure on the reins, she behaves great. If I need to correct her very much, she goes nuts.
So I plan to work her in the pasture with the curb chain adjusted tighter, and if that doesn't improve things, then I'll switch to a solid shank bit.