AutoLineBreak doesn't have to do anything with the editbox. Enter the text in the editbox on a single line, write it to a file with "!TexteditBoxExecute editboxlabel !xTextReplace @some file@ @theevar *@ @theevar "%[textinput]%"@". Have the file's text displayed on an label using "(Label)Text "$theevar$", and AutoLineBreak will put it in to multiple lines, depending on the size of the label's width, and the amount of text. And it would be a good idea to use autoheight for the label.

I've never tried this, but I can see no reason why it wouldn't work.