Musescore saves disasters automatically!

If Musescore makes a mistake, it's there permanently because when I close the file without saving, and then reopen, it's still there! Example: I have a file that is on one page and needs to stay that way. When I add slurs, Musescore adds more vertical space until eventually WHAM! the file is on two pages. I see no way to change it back to one page, but luckily I haven't saved the file with the mistake. In every other software I've seen, I just have to close and reopen and it's back to the file without the problem. Here, no matter what I do, the file is now two pages despite not saving what I've typed in. I've carefully saved numerous backup versions to return to in case a problem appears, and now I have ten versions of the file where I've tried numerous things over and over, and every time I try one thing that doesn't work, WHAM! it's two pages and I have to save more copies and do the file over again to try another solution. So: how do I keep it to one page, and how do I stop it from saving when I don't want to save mistakes? And after that is solved, I need to add another verse, which will expand the staff vertically. So right now I think the software will not achieve what I need, unless someone has an answer to both problems. Thanks for looking into this!