I have another little problem regarding this issue and I need your help again:
I finally opted for using wordwrap, and I assigned a limit of characters so that too long lines without spaces were cut.
But another issue comes up:
As the characters have different widths, 100 sequential m's on a line would be much longer than 100 i's. Thus, the limit of characters will always be either too short if there are many narrow characters with quite a long limit or too long if there are many wide characters with quite a short limit, showing either too short containing cells or overflown cells respectively.
Another suggestion to get around this?