unity Humanoid Animations Help

I have recently been introduced to Unity's humanoid system. My understanding is, if you have existing legacy animations(Generic), it will retarget them into humanoid animations which are muscle based.

I have two questions regarding the humanoid animations.

1. I used to be able to create new animations under window>animation. This doesn't work anymore as it's all through muscles and when I create a clip using transforms, it's ignored. I saw an asset on the asset store for creating muscle animations but I was curious if this can be done without any extensions. Is it possible to create new animation clips in Unity with their humanoid system?

2. For the sake of example, say I want to add a bend down or bend up on the character based off their look direction. In a generic rig, I would simply create an animation showing the character at the max look up angle and another for max look down angle and one final with him looking straight ahead and blend those based off a parameter. Can I still take this same approach in a humanoid rig? I noticed if every muscle position is not defined in a humanoid animation, it causes him to go into a strange pose.

Any help on these points would be appreciated. I should point out that the ONLY reason I am using a humanoid rig is to be able to use Unity's built in IK system for my weapon system.