Currently venues with seat maps don't show accurate amounts free. If there are multiple types, it'll show as like 42 available in the first group and then infinity in the others, so looking at the physical events list the % sold doesn't work. The workaround provided by Eventive support is to temporarily remove the venue, put capacity in each one (like it is a general admission site) and then re-add the venue.

There's also a related bug where just loading events that have assigned seats it'll show up in the admin like it doesn't have assigned seats. And then after changing almost anything it'll change and start to look like an assigned seat venue.