but it looks like all of the fields used for the checkboxes in that section are starting off with the value false instead of 0, and that's what's causing the NaN. It's possible to fix this by changing them all back in the Default Values dialog (on the Data tab),
This will help only until the first publishing or opening the template from sharepoint upon which Default 1 is reset to "TRUE" and 0 to "FALSE"
I would have changed the default of checkboxes to blank with "Treat blank values as zeros" in Form Options>Advanced. This prevents them from auto-resetting and errors in calculation
Though, what are the operands for creating boolean expressions. I tried "&" and "AND", they give errors