1: If you’re talking programatically, no, not as far as I know. You might be able to hack your way in through reflection, but you probably shouldn’t.
2: No
Both of these things might change with Unity 5, but probably not.
Usually, when people ask 2, it’s because they want the model to spawn in a certain animation pose that’s not the default one. If you’re doing that, you’ll want to hide the spawned object for one frame, use CrossFade with 0 as the transitionDuration parameter, and then make the object visible.
For 1. that would probably be a bad idea. If you need to change what animations your animator controller is using, and you’re changing more than 1, make a different controller with the same parameters. If it’s just one or two states that differ, just make it work with different states.