My roster builder spreadsheet is a complex creature, developed over several years, occasionally finding mistakes and frequently adding functionality. Sometimes the "adding functionality" actually "adds mistakes."
In developing a force the other day that had C3 and non-C3 units, I discovered that the C3 bonus was being added to units not partaking of the C3 network. That formula has now been fixed and thus version 5.0.1 now awaits your downloading pleasure.