The creche has been erected annually on the courthouse square by local Roman Catholic organizations since 1946. One group that helps make the display possible is a Knights of Columbus council, so I wonder if the national organization's finances and legal support will be drawn into the fight.
I have one more exam tomorrow, so I won't comment on the matter at length at this point.
However, a few quick, off-the-cuff observations:
I think it's cowardly for the Manitowoc County members of FFRF to refrain from being named plaintiffs in the suit. I also question whether they have been harmed in any way until they have sought and been denied a chance to place a display indicating their particular beliefs or lack thereof on the site (see the collection of holiday/winter displays at the Wisconsin State Capitol in the rotunda each year). Also, the complaint seems internally inconsistent, to some extent, as it first decries the lack of a policy about use of the site for religious displays and then proceeds to decry the dreadful policy of official approval later in the complaint. I am surprised that county officials didn't have some better scheme set up to handle a possible legal action based on the creche given a boatload of similar legally problematic scenarios out there (or maybe they do?). Finally, the lead case law cited in the complaint references a creche displayed inside a courthouse, not outside on the grounds of a courthouse, so I think that distinction might be important in any legal assessment under the First Amendment.
In addition, as far as context, I know from personal experience that there are a number of permanent monuments on the courthouse grounds, including a large stone monument to the Salomon Brothers. However, I can't recall the specific amount of religiosity or many other details about the monuments.
Here's a view of the courthouse and grounds from the LIB archives.