I've found a way to fix the menstrual cycle bug while we wait for the next update. Basically, you have to go into the debug room and manually start the cycle. This allows it to run properly in the apartment. It also eliminates the ovulation kit bug (the one where the affection is greater than or equal to 1). With these bugs fixed, the pregnancy system is much better than I initially thought, since I was finally able to make Mai have multiples. You're cooking up something good, dev!