Notes On Stations On Avatars
Don't Put Anything Into the "Enter/Exit Location"
This appears to cause the entire avatar to break and not load, I have no idea why, just don't do it. (This is possibly a bug?)
Don't Disable the Parent Gameobject
Don't animate the stuff in the red box, you can animate the stuff in the green boxes basically.
Forcing an Animation
Don't put your sitting animation on the base layer! Do it on a new layer, make sure to add a Tracking Control state behavior to enable and disable what you want tracked or not by VRChat if your animation needs to animate any of those specifically.