Update - survived the clinic. I didn't crash, puke, or die, so I'm apparently doing it wrong . Despite heavy rain all afternoon, it cleared up, and there were only a few spots that started to get muddy. We didn't use any singletrack, but with the clay soil we have here it would have made a mess of the trail to ride on it.
This was a group effort by the LBS, a local race team, the cx series organizer, and Raleigh USA. There were ~35 attendees, about a third were women. Good cross section of age, ability, cycling background, and type of bike.
Interestingly, the most common C&Vish rides there were Bianchis, I think I saw about 5 various cross/hybrid models.
I was kind of nervous driving over (usually ride since the park is only 4 miles away, but didn't want to ride home in the foggy dark with no lights), but everyone was very laid back and friendly.
No race this weekend for me due to brother-in-law getting married, but I'm going to try next weekend.