Insert "M_Precast-Rectangular Column with Corbels" column into project.
Hide some of the corbels.
Join column with floor (or attach top and etc).
Corbels reappear without possibility to hide them again.
This is known behavior that the development team is currently investigating; the visibility settings are lost when the column is joined to anything. Once the settings are lost they cannot be undone - a new column has to be placed. In the meantime, you may want to try to avoid actually joining it or try creating separate families for each representation.
I am sorry for the trouble that this causes to your workflow. Please let us know if there is anything we can do to help.
I reported it two versions back (RST 2011) and still the answer is the same...
Yes, this issue is not new to 2013. Unfortunately it has proven to be complex to address and the development team hasn't been able to resolve it yet. I apologize as I realize this certainly isn't ideal but I do assure you they are working to address it. I am very sorry in the meantime for having to work around it.