Bela's never really had a problem with other dogs - she loves them. The lady who was fostering her had her running the house with her other five Shelties, and she was fine being part of the pack. It's people she is skittish around. Not me, obviously, but there was a time when my husband (NOT dog people, and ex-military to boot) was a big, scary monster to her. He's been at home recovering from a heart ailment for the past six months, and she now will lay on him when she feels like it.
I was full of ambition for training her when I first got her. But after a couple of days I knew that was not to be. She just didn't have the confidence. And you really can't train a traumatized dog.
So right now, the only things she knows are what she's picked up. Unfortunately, come isn't one of them. She will gladly put her nose to a touch stick if it means food, and she knows what "wait", "ride", "hungry", "thirsty", and "sister" mean. She actually has a large vocabulary considering the lack of formal training.
She's loved any other dogs she's come across except for a very unruly pack of boxers she met in the dog park about a year ago. They ganged up on her and got a little rude, and she showed them her teeth. When they didn't stop, she growled as well, and was definitely not scared. But she acted appropriately, and I removed her from the situation as soon as possible. (And I got up in the boxer guy's face and yelled and made a huge scene because he was just laughing and refused to curb his dogs.)