Soft and Rigid bodies limitations
Limitation when passive rigid body parented to a hierarchy
Passive rigid body parented to a hierarchy may not interact correctly with active bodies and constraints
Put the same animation on the passive body, separate from the hierarchy.
Rigid bodies with negative scales and non-zero pivot points
Rigid bodies with negative scales and non-zero pivot points do not work properly. Duplicating rigid bodies with negative scales can lead to this situation.
Rigid bodies have a different playback result after saving the scene
The cycle involved with the rigid solver causes a different evaluation order. This problem has to do with to the DG evaluation order in a cycle.
Before you save the scene that contains rigid bodies, do the following:
Revolve limitation when converting to rigid bodies
Revolve can create an inside-out object when the surface is converted to a rigid body.
Digitize the curve in
clockwise direction, then select the curve and select
Surfaces > Revolve.
Or select
Edit NURBS > Reverse Surface Direction > 
and
reverse the U direction of the surface/generating curve.
To verify if the surface is inside-out, use single-sided lighting. Toggle off Lighting > Two Sided Lighting and toggle on Shading > Smooth Shade All. The surface will appear dark if it is inside-out.
Duplicate Input Graph limitation
Duplicate Input Graph does not work with rigid bodies.
Duplicate Input Graph also duplicates the rigid solver. Most likely this is not what you really want to do. If you just want a duplicate rigid body running off the same solver, turn off input connections and upstream graph checked then duplicate.
Use the Dynamic Relationship Editor to hook the rigid body up to any fields (you can also duplicate fields, if that is what you want to do.) If you really do want a second solver, you can make one at that point using the standard workflow for that operation (see the Dynamics guide for details).
Soft bodies and particles collide limitation
Soft bodies and particles may not collide well with objects modeled using large concave pieces of geometry (for example, the side of an outdoor stairway).