Physics behaviors halt after any PSD external updates.

[CrossTimber]

Greetings!

Just updated CH to the CC18 to try out the new physics behaviors.  The SAMPLE physics puppet is cool, but as soon as I change ANYTHING in the PDS, the physics cease.  I've restarted, refreshed, re-imported the fresh physics puppet; same problem every time.

To recreate this problem:

Download the Physics puppet.

Import into CH.

Open the CH Media > Gathered Media > PhysicsPlayground.psd

Make any change (hide & show a layer.)

Save it.

Return to CH.  It automatically updates the file.

Physics stop working... no gravity.  No movement.   I can drag some items which collide with SOME items, but not all.  Green puppet loses limbs, which eventually return to him.

Anyone have any suggestions?

Thank you!