readProperty does not call composeTypeImpl while readProperties does

Hi all, (and more specifically Peter)

returns the error: 678.991 [ ERROR ][refreshProperty] Could not
refresh nor compose Property SymmetricMatrix sysNoiseCovariance: type
mismatch, can not refresh with type PropertyBag

while, marshalling.readProperties(cpf/simulateBall.cpf") works just
fine and reads all my properties, including the sysNoiseCovariance.

When doing debugging I found that readProperty does not call
composeTypeImpl, while readProperties does ...

This bug is quite annoying, since I want to selectively update some
properties from a file (and not all of them) ...