I did a search on program content types with the following columns in the search model :

<column metadata-ref="title"/>
<column system-ref="contributor"/>
<column system-ref="contentLanguage"/>
<column system-ref="contentTypes"/>
<column system-ref="workflowStep"/>
<column metadata-ref="orgUnit/title"/>
<column system-ref="orgUnit/contributor"/>
<column system-ref="orgUnit/contentLanguage"/>
<column system-ref="orgUnit/contentTypes"/>
<column system-ref="orgUnit/workflowStep"/>

For the linked orgunits, the fields contentLanguage and workflowStep are not well displayed.
Also, "user" fields like contributor or creator are not well displayed if the user doesn't exist anymore. In the "normal" case, the cell is empty instead of undefined#undefined.

On Solr search tool, the workflowStep works but we have the same problem for other system fields.