I think it is simple and small bug, but anyway it is bug
for Navi Mesh Agent, I need to add "Rigid body" to Path-Finding Algorithm of Navigation Package in UnityEngine. unfortunately, Game Creator has its own Gravity algorithm (at "UpdateRootMovement" method of "ILocomotionSystem" class). because of this, if someone "sets" to use "gravity" options in the both (Character) and "rigidbody", the transform position will be keep falling even the character on the ground! the reason of this bug is very simple, because "rigidbody" and "Character" calculate "gravity" at same moment.
the simple solution of this problem is just "uncheck" gravity of "rigidbody", but I think it is not absolute solution. Game Mechanisms must be integrated for Game developers. I wish GC2.0 will make locomotion logics based on rigid body
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