How should I exit out out practice mode to ensure that ask data has been processed?

You mean to ensure that all your reviews are saved? You should hit next after your final review and then wait for the bar in the bottom right corner to turn green when you hover over it.

Pretty close. It isn't necessary to wait for it to turn green on hover, just for the little numbers to the left of it to go away. (Those numbers indicate how many items are in the process of being saved to the server.)

ah, right. I knew it was something like that.

Thanks!