Score changes after save

Hi Mark and thanks for responding. I have MuseScore 1.3 and mostly work on my Vista computer, occasionally on one running Windows 8.1.
I'm not feeling secure about posting the actual score, as I worry about someone taking my ideas. Maybe not necessary, but that's just me. I'll try to describe as best I can.
This is a series or exercise patterns. I wrote each out as a separate file. I gave each a title to indicate that this is A1, A2, and so on. There are a great number of them, so I want to save room where I can by merging each letter-name group into one file. Some patterns end in the middle of a page, so I'm trying to have the following pattern start in what would otherwise be blank (and wasted) space. I seemed to have it figured out: I would create a new score, copy and paste A1 into it and use text entry to show the name of the pattern. Then I used the spacer tool to give me enough room to put in the next name, A2, copy and paste in A2, and so on until I have A1 through A12 in one score (technically). Then on to the B's, etc.
I have been clicking and dragging the text to the just above the middle of the first staff of each exercise. When I finished all the A's, I save the file and close it. When I open it again, the text "titles" have moved, sometimes to the start of the line, sometimes to a whole other page.
I'm not sure but I just though of a possible reason just as I write this! I have been selecting the first note in the first line of each section and clicking ctrl+t to bring up the text tools. Could it be that I simply need to select a note that is already at the halfway mark. Hmm... Seems sort of obvious now.
I will try that and let you know what happens. If anything I've said tells you anything else about what I'm doing wrong, I always appreciate help.
Thanks, Mark in any case for being a sounding board. Sometimes that is a big help in itself.
Cheers!
Lenny