Attempting to save and duplicate a ship connected via Clockwork's physics bearings will cause both the duplicated ship and the original ship to disappear.
Using ship-to-ship connections in Vmod is fine, but it's extremely troublesome that problems occur when used simultaneously with Clockwork.

Modlist:
Clockwork 0.5.4.4
Create 6.0.8
Kotlin for Forge
Valkyrien Skies 2 2.4.6
Vmod 1.9.0