Yes! Of course, just make sure to mention them when you RSVP
Yes, there is a parking lot behind the Mabel Tainter Theater and plenty of on-street parking, which is free on the weekend.
No, not really. Wear what you feel comfortable in. We will likely be in chacos (but there will be photographs so do with that information what you will)
There are a few Air BNBs and VRBOs around. There is a hotel directly next to the theater (which we have a hotel block available for) or there are cheaper options off of I-94 just north of downtown Menomonie.