Matt, as discussed this morning, I cannot reproduce the strange behavior you observe. I have also tried with the gear cut wizard, as you asked me to do.
Have you actually used (i.e. pressed the calc button), one page before you reach the actual gear size and cut dimensions, the speed and feed calculation available ?
I have done so, obtain for my example a feed opf 240.1 mm/min which is nicely transported into the index.tap file.
Enjoy your evening, Philippe