1. You can schedule it on any day of the week and any time. See picture. And it is nifty because you can also schedule the start date and you can skip weeks.
2. What you do is schedule each XML seperately.
3. There is no FiFo strategy - or any other space management. When the space is full, it refuses to make more images. The space you have to manage yourself.
4. To tell you the truth, I have never used the Pro version. Not sure what it offers in addition. See here whether there is anything you like: http://www.macrium.com/reflectfree.aspx