I spoke with the church secretary at 1st Presbyterian in the village of Wappingers last night. She said we can have any meetings we'd like there. They won't charge us to use the space, although I suggested we'd make a nominal donation for use of the space.
They have two large meeting spaces: an auditorium with a stage and another large meeting room downstairs. They also have several smaller rooms. She suggested that Saturdays are better than Sundays as far as availability because a Hispanic church uses much of the building on Sunday afternoon/evening.
To book a space, I just need to give her 1-2 weeks advance notice and she will put us on the calendar.
The church is at 2568 South Ave, Wappingers Falls, NY 12590 (google map)