This is an especially late reply lol. I've been inactive for so long >.<
Eitherway. I personally don't believe you ever have to roll over. Ever.
I generally only played with the male, and got Mau Mau pregnant very easily. And at the time, being my first proper game, i had no idea U would do anything. So i didn't really care. I did like seeing the lioness roll over (they look cute and puppy like) after, so that's why i played the lion. And yep, she did have cubs.
The only noticeable thing for me was that both of them had to be full/quenched. Otherwise, everything else worked perfectly. With or without rolling over
.
And i kinda doubt there is such thing as a heat cycle? I admit i didn't play for so long, but i could always mate, regardless of rolling over or not. In fact, after the first cubs, i could immediately do so again (even with his own cubs... which was rather weird, so i doubt this game is intended to be so complicated).
As a side note. I'm glad to see more people take interest in playing! ^_^