How not getting my mesh exploding with Multifracture and PhysX shape

[Alexx31]

Hello,

testing the new Multifracture I'm getting immediately an exploding mesh (from penetration for sure).
I have set the penetration offset already very low (-1cm). ( And "Ignore starting penetrations" made also no difference)

Then I tried also operation "subtract volume", which is far easier to handle, but produces immediately visible rifts.
I need these cracks to be invisible before falling apart.

What can I do else?

Thanks