I am fiddling with the Betty Netch mesh, trying to make a large blue slime. I have figured out how to alter the bounding box, and have removed no bones.

When the mesh is an activator, it pulses and stays on the ground. But as a creature, it is above the ground. I want it to be on the ground like a proper slime.

I am thinking it may be the mian bone. (That is the spelling in Nifscope.) It is very tall, and seems to be what is keeping my slime floating above the ground, even though the slime is set to walk and not fly.

Is there a way to change the nifs for this creature so it doesn't float above the ground?

The problem is that it was animated as a creature that flies, so a lot of the keyframe animations include movement on the vertical axis. These seem to override whatever transform is on the node / shape that they are attached to, which makes editing them quite difficult. Short of someone writing a spell to transform keyframe data, your best bet might be to import the mesh into Blender / Max / etc. and redo the animations there.